delivered the opinion of the court:
Defendant, Jose Garcia, was charged with one count of unlawful possession of marijuana (Ill. Rev. Stat. 1973, ch. 56½, par. 704), one count of unlawful possession of cocaine (Ill. Rev. Stat. 1973, ch. 56½, par. 1402), and four counts of failure to register a firearm (Chicago, Ill., Code 1973, ch. 11.1, par. 11.1 — 7). Defendant’s arrest and the seizure of the contraband stemmed from a search warrant issued November 13,1972, to search defendant and the second-floor apartment at 918 N. Pulaski Rd., Chicago, and seize a controlled substance (cocaine). Defendant’s motion to quash the search warrant was granted by the circuit court of Cook County. The State now, pursuant to Supreme Court Rule 604(a)(1), appeals that order. Ill. Rev. Stat. 1973, ch. 110A, par. 604(a)(1).
The search warrant in question was issued on November 13, 1972, on a complaint filed that same day by Officer Bernard Brown of the Chicago Police Department. In his complaint for a search warrant Officer Brown filed the following affidavit:
“I, Bernard Brown, a police officer for the City of Chicago had a conversation on the 12 November 1972 with a reliable police informer relative to narcotic violations. I have known this police informer for the past three years as a user of drugs. During the past three years I have had five conversations with the reliable police informer relative to narcotic violations and on each of these five occasions narcotic contraband was recovered. Of the five cases made by the reliable information of the reliable police informer three cases ended in convictions in the criminal court and 2 cases were B.F.W.1 During my conversation with the reliable police informer on the 12 November 1972 he stated to me that on the 12 November 1972 reliable police informer was in the 2nd floor apt. located at 918 N. Pulaski Road and while there purchased a tin foil packet of cocaine from male Mexican known as Joe Garcia as above described for the sum of $50.00 USC. Rehable police in*398former has been a user of cocaine drugs for the past eight years and should be considered an expert as to what cocaine is the feeling received from taking the cocaine. Reliable police informer further stated to me when leaving said premises located at 918 N. Pulaski Road 2nd floor front apt. said M/Mex known as Joe Garcia still had a larger quantity of cocaine in his immediate possession and under his direct control. This building was kept under surveillance on the 12 November 1972 by Inv. R. McKelvey who observed many males and females of Spanish descent entering and emerging from said apt. and many of them were known as users of drugs to said investigator.”
At the hearing on the motion to quash, defendant did not challenge the first requirement, namely, that the affidavit sufficiently establish that the informant was reliable. The absence of such an attack is not surprising, since the affidavit clearly established the informant’s reliability— previous information resulting in three convictions and two B.F.W.’s. People v. Portis, 4 Ill.App.3d 333, 280 N.E.2d 712; People v. Cook, 133 Ill.App.2d 335, 273 N.E.2d 261.
However, defendant did vigorously challenge the second requirement, namely, that the affidavit establish sufficient facts from which the informant concluded that narcotics were where he claimed they were. SpecificaUy, defendant argues that the affidavit failed to allege exactly how the informant knew that what he purchased was cocaine. Defendant argues that as to both requirements, the.affidavit states bald conclusions and not underlying facts.
Defendant argues that the affidavit does not state that the informant actually used the substance he bought from defendant to determine that it was, in fact, cocaine. Rather, the affidavit merely states:
“[Informant] while there purchased a tin foil packet of cocaine from male Mexican known as Joe Garcia as above described for the sum of $50.00 USC.”
The State argues that the next sentence of the affidavit—
“Reliable police informer has been a user of cocaine drugs for the past eight years and should be considered an expert as to what cocaine is the feeling received from taking the cocaine.”
—clearly indicates that since the informant was an “expert drug user,” his mere statement that he purchased cocaine should be sufficient.
While it can hardly be denied that the affidavit could be written with greater clarity, the personal purchase by the informant, an “expert drug user,” is sufficient. In People v. Ranson, 4 Ill.App.3d 953, 955, 282 N.E.2d 462, the officer’s affidavit similarly stated:
“‘[Informant] while there bought from a male Negro known to *399him as “Boot” a packet of heroin for the sum of $25.00 in United States currency. * # *’ ”
The court in Ramon found the affidavit sufficient stating:
“The affidavit of officer Nance set forth underlying circumstances which would justify the conclusion that Ida Ranson was in the possession of heroin. The informant was recently in the apartment identified in the complaint; he purchased a packet of heroin and Ranson possessed some heroin after the transaction. Although these allegations were uncorroborated, they were sufficiently detailed to enable the magistrate to ascertain how the informant acquired his information and to determine the probability that a quantity of narcotics was still in the apartment.” (4 Ill.App.3d 953, 955.)
Likewise in People v. Rivera, 130 Ill.App.2d 321, 322, 264 N.E.2d 699, the officer’s affidavit stated:
“1 [Informant-affiant] while in said apartment saw in the immediate possession and under the direct control of one female negro known to me as Scott (Doe) a quantity of narcotics known as heroin. From this quantity of heroin this female negro known to me as Scott (Doe) sold and delivered to me one tinfoil package of heroin for the sum of $25.00 United States Currency.”
The court in Rivera also found that affidavit sufficient stating:
“The complaint states that the affiant personally purchased narcotics at the place identified therein from a woman known to him as Scott, and when he left the apartment heroin was in the immediate possession and direct control of the woman from whom he made the purchase of narcotics. We find the warrant was issued on probable cause * * 130 Ill.App.2d 321, 328.
Thus, the court could rely solely on Ramon and Rivera and hold that the affidavit was sufficient to inform the issuing magistrate of the facts underlying the informant’s conclusions that what he personally purchased was cocaine.
Moreover, there is additional helpful language present in the instant affidavit that was not available to the courts in Ramon and Rivera. The present affidavit alleges that the informant was a drug user for 8 years and was an expert in what was cocaine. Additionally, there is language in the present affidavit, although admittedly vague, that the instant informant did actually use the cocaine purchased. Note:
“a # * should be considered an expert as to what cocaine is the feeling received from taking the cocaine.” (Emphasis supplied.)
The definite article “the” seems to refer to the cocaine purchased and not cocaine generally. On the basis of this additional support together *400with Ranson and Rivera, we conclude that the defendant’s first argument is unpersuasive.
Defendant next challenges the sufficiency of the affidavit’s allegation that cocaine was still present in defendant’s premises when the informer left. He notes the following language:
“[W]hen leaving said premises * ** 6 Jose Garcia still had a larger quantity of cocaine in his immediate possession and under his direct control.”
Defendant again contends that this is a mere conclusion. The short answer is that again in both Ranson and Rivera substantially similar allegations were found sufficient — as indicated by the above cited language. Thus, we conclude that merely on the basis - of Ranson and Rivera the affidavit was sufficient to establish probable cause for issuance of the search warrant.
Moreover, apart from Ranson and Rivera, there is additional support for finding the affidavit sufficient. For, it should be noted that the instant affidavit contains some corroboration by police officers. While it is admittedly weak, the affidavit does state:
“This building was kept under surveillance on the 12 November 1972 by Inv. R. McKelvey who observed many males and females of Spanish descent entering and emerging from said apt. and many of them were known as users of drugs to said investigator.”
It is clear that an affiant may base his request upon the information received from fellow officers who are engaged in a common investigation. (United States v. Ventresca, 380 U.S. 102; People v. Levin, 12 Ill.App.3d 879; 299 N.E.2d 336.) In People v. Neal, 12 Ill.App.3d 525, 299 N.E.2d 532, the court applied the same rule and pointed to corroboration of the same type, that is, an officer’s observation of people going in and out of defendant’s premises and found probable cause.
Probable cause is only a reasonable belief that an offense has been committed and that the defendant committed it. The affidavit must only inform the issuing magistrate of the facts relied on by a complaining officer to show probable cause. (People v. Tate, 44 Ill.2d 432, 255 N.E.2d 411.) Search warrants must be tested and interpreted by magistrates and courts in a common-sense and realistic fashion lest police officers, who frequently draft them, be discouraged from submitting their evidence to a judicial officer before acting. The order quashing the search warrant is reversed and the cause remanded for further proceedings.
Reversed and remanded.
DOWNING, P. J., concurs.