An information charged defendant and Frank Harper with seven counts of forgery and two counts of grand theft. Defendant and Harper waived trial by jury and stipulated that the trial judge decide the ease on the transcript of the preliminary hearing. The trial court found defendant guilty of one count of forgery and dismissed the other eight counts against defendant. Defendant appeals.

We hold that (1) an arrest warrant issued solely upon the complainant’s “information and belief” cannot stand if the complaint or an accompanying affidavit does not allege underlying facts upon which the magistrate can independently find probable cause to arrest the accused; (2) sections 806, 813, and 952 of the Penal Code do not authorize the issuance of warrants of arrest based solely upon complaints couched in the language of the charged offense and therefore do not violate the Fourth Amendment; (3) handwriting exemplars taken incidental to an illegal arrest are inadmissible; (4) the admission of defendant’s handwriting exemplars constituted prejudicial error.

On January 12, 1966, Police officer Hargraves signed a nine-page felony complaint. 1 On the same day, a judge of the municipal court issued a warrant for the arrest of defendant *422 and Harper. On the next day Officer Hargraves, acting pursuant to the warrant, arrested defendant in his office. Hargraves advised defendant of his right to counsel and his right to remain silent and further informed him that he did not have to give any handwriting exemplars. At Hargraves’ request, however, defendant wrote out an exemplar. Later, at the police station, he gave further exemplars.

An expert witness testified that the handwriting on the exemplars and the handwriting on the forged $5,800 cheek were executed by the same person. This testimony comprised the only evidence establishing that defendant signed the fictitious name on the check. Although defendant offered timely objections to the admissibility of the exemplars, the trial court permitted their introduction on the ground that the prosecution obtained them as an incident to a valid arrest and during defendant’s legal detention.

I.

The Fourth Amendment requires that “no Warrants shall issue, but upon probable cause, supported by Oath or Affirmation. . . ,” 2 3In Giordenello v. United States (1958) 357 U.S. 480 [ 2 L.Ed.2d 1503 , 78 S.Ct. 1245 ], the United States Supreme Court held that a complaint which merely stated the affiant’s conclusions couched in the words of the statute 3 cannot support a valid arrest warrant. Justice Harlan said: *1 The purpose of the complaint, then, is to enable the appropriate magistrate, ... to determine whether the ‘probable cause’ required to support a warrant exists. The Commissioner must judge for himself the persuasiveness of the facts relied on by a complaining officer to show probable cause. He should not accept without question the complainant’s mere conclusion that the person whose arrest is sought has committed a crime. *423 . . . [Here] the complaint contains no affirmative allegation that the affiant spoJce with personal knowledge of the matters contained therein; it does not indicate any sources for the complainant’s belief; and it does not set forth any other sufficient basis upon which a finding of probable cause could be made.” (Italics added.) (Id. at p. 486 [2 L.Ed.2d at pp. 1509-1510].)

Although the Attorney General correctly points out that Giordenello rested on the federal rules of criminal procedure applicable to a federal prosecution, Aguilar v. Texas (1964) 378 U.S. 108 [ 12 L.Ed.2d 723 , 84 S.Ct. 1509 ], grounded these rights in the Constitution. In that case, which involved a search warrant issued by a Texas justice of the peace, the United States Supreme Court said, “The principles announced in Giordenello derived, therefore, from the Fourth Amendment, and not from our supervisory power.” (Id. at p. 112 fn. 3 [ 12 L.Ed.2d at p. 727 ].) The court also determined that Ker v. California (1963) 374 U.S. 23 [ 10 L.Ed.2d 726 , 83 S.Ct. 1623 ], which stated that “the standard of reasonableness is the same under the Fourth and the Fourteenth Amendments” ( 374 U.S. at p. 33 [ 10 L.Ed.2d 738 ]), “must certainly be read as holding that the standard for obtaining a search warrant is likewise ‘the same under the Fourth and Fourteenth Amendments. ’ ” ( 378 U.S. at p. 110 [ 12 L.Ed.2d at p. 726 ].)

Aguilar held that, “Although an affidavit may be based on hearsay information and need not reflect the direct personal observations of the affiant, . . . the magistrate must be informed of [1] some of the underlying circumstances from which the informant concluded that the narcotics were where he claimed they were, and [2] some of the underlying circumstances from which the officer concluded that the informant, whose identity need not be disclosed, . . . was ‘ credible ’ or his information was ‘reliable.’ Otherwise, ‘the inferences from the facts which lead to the complaint’ will be drawn not ‘by a neutral and detached magistrate,’ as the Constitution requires, but instead, by a police officer ‘engaged in the often competitive enterprise of ferreting out crime, ’ Giordenello v. United States.” (Id. at pp. 114-115 [ 12 L.Ed.2d at p. 729 ].)

In Barnes v. Texas (1965) 380 U.S. 253 [ 13 L.Ed.2d 818 , 85 S.Ct. 942 ], in a case involving an arrest warrant, the Supreme Court in a per curiam opinion cited Giordenello and *424 Aguilar as the sole basis for reversal of the conviction. 4 Barnes demonstrates that Oiordenello and Aguilar must be read together as formulating the requirements of the Fourth Amendment for valid arrest as well as search warrants, and that the standards set forth in Giordenello , as clarified in Aguilar, United States v. Ventresca (1965) 380 U.S. 102 [ 13 L.Ed.2d 684 , 85 S.Ct. 741 ] ; and Jaben v. United States (1965) 381 U.S. 214 [ 14 L.Ed.2d 345 , 85 S.Ct. 1365 ], apply to the states through the Fourteenth Amendment. (Ker v. California, supra, 374 U.S. 23 .)

In Jaben the United States Supreme Court classified the types of factual showing required to meet the constitutional standards. In that ease, which involved a summons ordering the defendant to appear at a preliminary hearing, the Supreme Court said that “Information in a complaint alleging the commission of a crime falls into two categories: (1) that information which, if true, would directly indicate commission of the crime charged, and (2) that which relates to the source of the directly incriminating information.” ( 381 U.S. at p. 223 [ 14 L.Ed.2d at p. 352 ].) This classification directly parallels and clarifies the two types of underlying circumstances which Aguilar held that a complaint must state in order to support a valid search warrant under the Fourth Amendment.

If such a complaint, supporting an arrest warrant, does not allege the two types of facts delineated by Aguilar and Jaben , the warrant fails and an arrest made pursuant to it is *425 illegal. (Barnes v.. Texas, supra, 380 U.S. 253 .) 5 Here the complaint did not state (1) any facts which would support the complainant’s belief that defendant had committed any felonies as alleged, or (2) any facts relating to the identity or credibility of the source of the complainant’s information.

The Attorney General’s attempt to distinguish this complaint from those held insufficient to support a valid arrest warrant in Giordenello and Barnes on the basis that the complaint concludes with a list of “Witnesses” thus misses the mark. The complaint did not allege that any of the listed persons were the source of the information upon which the complainant relied in seeking a warrant for defendant’s arrest, or allege any facts connecting defendant with the charged forgeries as to which the “witnesses” could testify. That a number of persons can testify to the crimes alleged in a complaint does not constitute the type of allegation which enables a “neutral and detached” magistrate independently to determine on the basis of the evidence before him that probable cause supports the arrest of the person charged in the complaint. (Aguilar v. Texas, supra, 378 U.S. at pp. 109 fn. 1, 111-115 [12 L.Ed.2d at pp. 725, 726-729] ; Giordenello v. United States, supra, 357 U.S. at pp. 486-487 [2 L.Ed.2d at pp. 1509-1510].)

II.

California’s statutory scheme authorizing the issuance of arrest warrants does not violate the Fourth Amendment. When the relevant provisions (Pen. Code, §§806, 813, and 952) 6 are read together and construed in light of Giordenello-Aguilar, they meet the constitutional test. A complaint based on “information and belief” and couched in the statutory language of the alleged offense may support a *426 valid arrest warrant if the complaint alleges sufficient facts for the magistrate to conclude that probable cause supports the warrant in that the allegations indicate (1) the commission of the crime by the person whose arrest is sought, and (2) the reliability of the information and credibility of its source.

Section 813 of the Penal Code provides that the magistrate must issue an arrest warrant if he “is satisfied from the complaint” that “there is reasonable ground” to arrest the defendant. Giordenello-Aguilar requires that the magistrate may issue an arrest warrant only if he is satisfied from the complaint that there is probable cause to arrest the defendant. The statutory mandate does not conflict with the constitutional standard; the former must be construed in light of the latter. So interpreted, section 813 provides in effect that an arrest warrant shall issue if, and only if, “such magistrate is satisfied from the complaint that the offense complained of has been committed and that there is reasonable ground to believe that the defendant has committed it. ’ ’

That the complaint is based on “information and belief” rather than personal knowledge of the affiant (§806), or phrased in terms of the statutory language of the alleged offense (§ 952) does not resolve the issue. The crucial factor lies not in the form of the allegations, but in the sufficiency of the facts alleged “to enable the appropriate magistrate, . . . to determine whether the 1 probable cause ’ required to support a warrant exists.” (Giordenello v. United States, supra, 357 U.S. at p. 486 [ 2 L.Ed.2d at p. 1509 ] ; Aguilar v. Texas, supra, 378 U.S. at p. 115 [12L.Ed.2d atp. 729].)

III.

The admission into evidence of the handwriting exemplars procured after defendant’s arrest and during his illegal detention violated his rights under the Fourth Amendment. The state may not use evidence to convict an *427 accused which it obtained by exploiting an illegal arrest or detention. (Wong Sun v. United States (1963) 371 U.S. 471, 484-485 [ 9 L.Ed.2d 441, 453-454 , 83 S.Ct. 407 ] ; Mapp v. Ohio (1961) 367 U.S. 643, 655 [ 6 L.Ed.2d 1081, 1090 , 81 S.Ct. 1684 , 84 A.L.R.2d 933 ] ; Silverthorne Lumber Co. v. United States (1920) 251 U.S. 385, 392 [ 64 L.Ed. 319, 321 , 40 S.Ct. 182 , 24 A.L.R. 1426 ] ; People v. Stoner (1967) 65 Cal.2d 595, 598 [ 55 Cal.Rptr. 897 , 422 P.2d 585 ] ; People v. Bilderbach (1965) 62 Cal.2d 757, 763 [ 44 Cal.Rptr. 313 , 401 P.2d 921 ] ; People v. Cahan (1955) 44 Cal.2d 434, 445-450 [ 282 P.2d 905 , 50 A.L.R. 2d 513 ].)

In People v. Bilderbach, supra, 62 Cal.2d at p. 766 , we held that Ker v. California, supra, 374 U.S. 23 , required us to apply the test in Wong Sun v. United States, supra, 371 U.S. 471 , to determine the admissibility of evidence obtained as a result of an illegal arrest, search, or seizure. Here the police obtained a handwriting exemplar shortly after arresting defendant at his office pursuant to an invalid warrant and then required further exemplars after taking him to the police station. As we explained in Bilderbach , the Supreme Court in Wong Sun held that an illegal arrest immediately preceding the procurement of evidence “rendered [that evidence] inadmissible as the ‘fruit’ of the agents’ illegal action. . . . Under such circumstances it is unreasonable to infer that [defendant’s] response was sufficiently an act of free will to purge the primary taint of the unlawful invasion.” ( 62 Cal. 2d at p. 765 .) The handwriting exemplars were thus “come at by exploitation of [the] illegality” (Wong Sun v. United States, supra, 371 U.S. at p. 488 [ 9 L.Ed.2d at p. 455 ]) of the arrest and detention. The admission of the exemplars would therefore “thwart the laudable policies underlying the exclusionary rule.” (People v. Bilderbach, supra, 62 Cal.2d at p. 768 ; see also Bynum v. United States (D.C. Cir. 1959) 262 F.2d 465, 466-467 [ 104 App.D.C. 368 ] ; State v. Miller (1966) 76 N.M. 62 [ 412 P.2d 240, 244 ].)

*428 We find no basis upon which to conclude that the connection between the exemplars and the illegal arrest has “become so attenuated as to dissipate the taint.” (People v. Bilderbach, supra, 62 Cal.2d at p. 766 .) As the Supreme Court explained in Wong Sun , “not ... all evidence is ‘fruit of the poisonous tree’ simply because it would not have come to light but for the illegal actions of the police. Rather, the more apt question in such a case is ‘whether, granting establishment of the primary illegality, the evidence to which instant objection is made has been come at by exploitation of that illegality or instead by means sufficiently distinguishable to be purged of the primary taint.’ ” ( 371 U.S. at p. 488 [ 9 L.Ed.2d at p. 455 ].)

That degree of “attenuation” which suffices to remove the taint from evidence obtained directly as a result of unlawful police conduct requires at least an intervening independent act by the defendant or a third party which breaks the causal chain linking the illegality and evidence in such a way that the evidence is not in fact obtained “by exploitation of that illegality.” Consent by the defendant, if “sufficiently an act of free will to purge the primary taint of the unlawful [arrest] ” (Wong Sun v. United States, supra, 371 U.S. at p. 486 [ 9 L.Ed.2d 454 ]), may produce the requisite degree of “attenuation.”

The prosecution urges that there was an intervening act of free will between the illegal arrest and the procurement of the handwriting exemplars that dissipated the taint of the primary illegality. The trial court, however, made no finding that the prosecution sustained its burden 7 of showing that defendant freely gave the exemplars. (See People v. Bilderbach, supra, 62 Cal.2d 757, 763 ; cf. People v. Henry (1967) 65 Cal.2d 842, 846 [ 56 Cal.Rptr. 485 , 423 P.2d 557 ].)

Moreover, on the basis of the record before us we could not characterize as unreasonable an inference that the connection between the illegal arrest and the procurement of the exemplars lacked the requisite attenuation. Defendant produced the first exemplar shortly after the illegal arrest. This illegality tends to vitiate any claimed consent in two respects: (1) the arresting officer secured entry to defendant’s office under the purported authority of a warrant, and the entry may have been essential to obtaining consent; (2) *429 the consent may have been dictated by an implied assertion of authority by the officer. (See People v. Haven (1963) 59 Cal. 2d 713 [ 31 Cal.Rptr. 47 , 381 P.2d 927 ].)

We have noted, supra, Officer Hargraves’ testimony that prior to obtaining the first exemplar he informed defendant that he had a right to remain silent, a right to counsel at all stages of the proceedings, and a right not to give any handwriting exemplars. 8 Since the rendition of exemplars does not amount to self-incrimination within the meaning of the Fifth Amendment, these warnings were not required for the protection of defendant’s Fifth Amendment rights. (Gilbert v. California (1967) 388 U.S. 263, 266-267 [ 18 L.Ed.2d 1178, 1182 , 87 S.Ct. 1951 ] ; People v. Graves (1966) 64 Cal.2d 208, 210-211 [ 49 Cal.Rptr. 386 , 411 P.2d 114 ].) We must consider, however, whether the officer’s advice and defendant’s response makes unreasonable as a matter of law the inference that the officer secured the incriminating evidence through exploitation of his violation of defendant’s Fourth Amendment rights.

The rendition of similar advice, as an added safeguard to insure defendant’s voluntary waiver of his constitutional rights, does not, in itself, preclude application of the Wong Sun exclusionary rule. Thus in People v. Bilderbach, supra, 62 Cal.2d 757 , defendant contended that his confession was inadmissible both because the record did not indicate that the officers had complied with the requirements of People v. Dorado (1965) 62 Cal.2d 338 [ 42 Cal.Rptr. 169 , 398 P.2d 361 ], and because the confession constituted the “fruit” of an illegal search. We held that even in the event that the prosecution upon retrial could establish that defendant intelligently waived his Dorado rights prior to giving the confession, the trial court would still be required to determine whether the taint from the illegal search had been dissipated. 9 *430 In Wong Sun itself, the United States Supreme Court had to determine whether Wong Sun’s confession was the “fruit” of an illegal arrest. In its statement of facts the court noted that prior to his confession an agent of the Narcotics Bureau had advised him of his right to counsel and his right to remain silent. ( 371 U.S. at p. 476 [ 9 L.Ed.2d at p. 448 ].) In holding that the illegal arrest did not taint the confession, the court, however, relied solely “ [o]n the evidence that Wong Sun had been released on his own recognizance after a lawful arraignment, and had returned several days later to make the statement . . . .” (P. 491 [ 9 L.Ed.2d at p. 457 ].) We conclude, therefore, that although the advice given in the instant case may be a factor showing an intervening act of free will (cf. People v. Stoner, supra, 65 Cal.2d 595, 600 ), it does not in isolation demonstrate as a matter of law the requisite attenuation.

Defendant furnished the second set of exemplars while illegally detained and with the knowledge that the People already had one sample of his handwriting. “ [T]he compulsion inherent in custodial surroundings” (Miranda v. Arizona (1966) 384 U.S. 436, 458 [ 16 L.Ed.2d 694 , 86 S.Ct. 1602 , 10 A.L.R.3d 974 ]), especially when considered in conjunction with the prior illegally obtained exemplar (see Fahy v. Connecticut (1963) 375 U.S. 85, 90-91 [ 11 L.Ed.2d 171, 175 , 84 S.Ct. 229 ] ; People v. Spencer (1967) 66 Cal.2d 158, 163-168 [ 57 Cal. Rptr. 163 , 424 P.2d 715 ]), precludes our holding as a matter of law that the prosecution sustained its burden of showing that defendant freely consented to the officers’ procurement of the second set of exemplars.

If the question of the admissibility of the exemplars should arise upon retrial, the prosecution and the defense may introduce further evidence bearing on this question. (Cf. People v. Doherty (1967) 67 Cal.2d 9 , 17 fn. 7 [ 59 Cal.Rptr. 857 , 429 P.2d 177 ] ; People v. Green (1965) 63 Cal.2d 561, 565 [ 47 Cal.Rptr. 477 , 407 P.2d 653 ].) In such event, the trial court will determine the admissibility of the exemplars upon its examination of the facts in accordance with the above principles.

The prosecution’s only evidence that defendant signed the forged cheek consisted of the handwriting expert’s testimony that the signature on the check and the handwriting exemplars were executed by the same person. The admission into evidence of the handwriting exemplars *431 obtained in violation of defendant’s rights under the Fourth Amendment therefore constituted prejudicial error.

In sum, in holding that an arrest warrant issued solely upon the complainant’s “information and belief” cannot stand if the complaint or accompanying affidavit does not allege underlying facts upon which the magistrate can independently find probable cause to arrest the accused, we do no more than apply constitutional principles long held and clear!)' expressed by the decisions of the United States Supreme Court. To do less would be to expose our ruling to the unanswerable charge of constitutional infirmity.

The judgment is reversed.

Traynor, C. J., Peters, J., and Sullivan, J., concurred.

The first page of the complaint states; “Jack Hargraves of the County of Los Angeles who, being first duly sworn on oath, upon information and belief complains and says: That on or about the 16th day of December, 1965, at and in the county of Los Angeles, State of California the crime of Forgery of Fictitious Name, in violation of Section 470, Penal Code, a felony was committed by Gerald Sesslim and Frank Wesley Wright Harper who, at the time and place last aforesaid, did wilfully, unlawfully, fraudulently and feloniously make, pass, utter and publish a certain fictitious check and order in writing for the payment of money in the sum of Four Hundred fifty-seven and 00/100 Dollars $457.00 knowing said check to be fictitious, as aforesaid, with intent then and there to cheat and defraud Nellie Allen, Commerce Dank, and Handy Payments, a corporation. Said complainant therefore prays that a warrant may be issued for the arrest of the defendant who may then be dealt with according to law.” The italicized portions are those filled in by the complainant Hargraves. The rest of the complaint is a printed form. Each of the remaining eight pages of the complaint relates to one of the remaining eight counts, regarding other fictitious checks allegedly made and passed by defendant and Harper. Each page duplicates the first page of the complaint except for differences in the amount of the check involved and the names of the persons allegedly defrauded. Page 3 of the complaint relates to the $5,800 cheek which served as the basis of defendant’s conviction.

The California Constitution and the Penal Code eontaii similar provisions. Article I, section 19 of the California Constitution states that “. . . no warrant shall issue, but on probable cause, supported by oath or affirmation, ...” Section 813 of the Penal Code provides: ‘‘When a complaint is filed with a magistrate charging a public offense originally triable in the superior court of the county in which he sits, if such magistrate is satisfied from the complaint that the offense complained of has been committed and that there is reasonable ground to believe that the defendant has committed it, he must issue a warrant for the arrest of the defendant; ...” (Italics added.)

The complaint in Giordenello stated: ‘ ‘ The undersigned complainant [Finley] being duly sworn states: That on or about January 26, 1956, at Houston, Texas in the Southern District of Texas, Veto Giordenello did receive, conceal, etc., narcotic drugs, to-wit: heroin hydrochloride with knowledge of unlawful importation; in violation of Section 174, Title 21, United States Code.”

The Texas Court of Criminal Appeals held the following warrant valid on the assumption that Giordenello did not apply to the states: “That heretofore, to-wit: on or about the 29th day of May, A.D. 1962, and before the making and filing of this Complaint, in the County of Lubbock and State of Texas, Billy Joe Barnes and Johnny Leach did then and there unlawfully and fraudulently take from the possession of Southwestern Bell Telephone Company herein called ‘owner’ good and lawful United States currency of the value of over Fifty and No/100 ($50.00) dollars, the same then and there being the corporeal personal property of the said ' owner, ’ . . . without the consent of the said ‘owner,’ and with the intent then and there to deprive the said ‘owner’ of the value of the same, and to appropriate same to the use and benefit of them, the said Billy Joe Barnes and Johnny Leach against the peace and dignity of the State.” (Barnes v. State (Tex.Crim.App. 1964) 390 S.W.2d 266, 269 .)

The complaint in Barnes, like the complaints here and in Giordenello , is defective in that it merely sets forth the terms of the statute violated and does not allege any underlying facts from which a magistrate could conclude that there was probable cause to believe that the defendant had committed the alleged offense.

The record contains no evidence that Officer Hargraves had probable cause to arrest defendant. We therefore need not reach the question whether there are circumstances under which an arrest made pursuant to an invalid warrant may nonetheless be legal. (Cf. People v. Chimel, post, p. 436 [ 67 Cal.Rptr. 421 , 439 P.2d 333 ].)

Section 806 provides: “A proceeding for the examination before a magistrate of a person on a charge of an offense originally triable in a superior court must be commenced by written complaint under oath subscribed by the complainant and filed with the magistrate; . . . Such complaint may be verified on information and belief.” (Italics added.)

Section 952 provides: “In charging an offense, each count shall contain, and shall be sufficient if it contains in substance, a statement that the accussed has committed some public offense therein specified. Such *426 statement . . . may he in the words of the enactment dese-rihmg the offense. ...” (Italics added.)

Section 813 provides that a magistrate must issue a warrant for the arrest of the defendant “if such magistrate is satisfied from the complaint that the offense complained of has been committed and that there is reasonable ground to believe that the defendant has committed it. ’ ’

Section 813 does not explicitly state that a magistrate may not issue an arrest warrant if the complaint does not allege sufficient facts from which he can independently determine that there is probable cause to arrest the defendant. (Cf. Giordenello v. United States, swpra, at p. 486 [2 L.iidffd at p. 1509].) Moreover, the Penal Code nowhere prescribes *427 the contents of a complaint which would require the issuance of an arrest warrant under section 813. As the Attorney General point, c- t, however, reliance in the past has been placed on sections 806 and 952 to determine the nature of the complaint, sufficient to obtain a warrant under section 813. Although such reliance contravenes the Giordenello-Aguilar rule, sections 806 and 952 are not thereby rendered unconstitutional. Sections 806 and 952 directly relate to accusatory complaints, not complaints to support a warrant. Giordenello-Agmlar merely teaches that we not construe these sections to provide that complaints drawn in compliance with them are automatically sufficient to support a valid arrest warrant.

Castaneda v. Superior Court (1963) 59 Cal.2d 439, 443-444 [ 30 Cal. Rptr. 1 , 380 P.2d 641 ] ; People v. Gorg (1955) 45 Cal.2d 776, 782 [ 291 P.2d 469 ].

Hargraves advised defendant “that he was entitled to remain silent, that he did not have to tell this investigator anything or answer any questions that I might ask, that he was entitled to an attorney at all stages of the proceedings, including that interview and any interview I might have with him, that he did not have to give me any handwriting exemplars, that if he did give me any handwriting [exemplars], that they would probably or might be used against him in court in a criminal proceeding. ’ ’

We noted that “ [e]ven though statements are free of ‘oppressive circumstances’ and otherwise voluntarily rendered, they are not exempt from attack on constitutional grounds if they are the product of an illegal search.” (People v. Bilderbach, supra, 62 Cal.2d 757, 767 .)