Philip Seymour Hoffman -- Two Alleged Drug Dealers Targeted in Police Raid

New York cops have just made 4 ARRESTS in connection with Philip Seymour Hoffman's death … Law enforcement sources familiar with the situation tell TMZ.

Our sources tell us … police have obtained a search warrant and are currently on scene at a NY apt. We're told police are targeting two individuals who they believe sold PSH heroin.  Sources say cops raided 3 units in the same building.

Sources also tell us … someone involved in the heroin market in NYC contacted police and gave them the names and addresses of two alleged drug dealers who pushed the drug.

We're told the heroin user told cops he buys from the same dealer Hoffman frequented and sometimes saw Hoffman in the dealer's apartment.  The informant says Hoffman would buy "bundles" of heroin at a time ... twice a week.

Sources say the informant told cops ... the alleged dealer -- a musician for a famous rapper -- would sometimes run out of his supply and use a secondary dealer, who sold "cheap s**t heroin" that was dangerous.  And the informant says ... Hoffman would get the secondary supply.

Four suspects are now in custody.  Law enforcement tells us all 4 were arrested for drugs found in the apartment units.


10:15 PM PT -- Sources tell us 3 of the suspects are men ... 1 woman -- and officers found nearly 350 glassine baggies filled with heroin.  We're told one of the men -- Robert Vineberg has played sax for Mick Jagger, Amy Winehouse, Wyclef, Tom Jones and David Bowie. He's been charged with felony drug possession.

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