Street ball legend Fly Williams -- considered one of the greatest street ballers of all time -- was arrested in NY after cops say he was running a multi-million dollar heroin empire.
The 64-year-old -- who was drafted by the Denver Nuggets in the 1st round of the '74 ABA Draft -- has named the "kingpin" of the operation by the Brooklyn District Attorney.
He's facing 10 felony charges related to the alleged ring.
Law enforcement sources tell us prosecutors believe Fly was running a team of street dealers who were moving 2 million glassines of heroin at $10 a pop.
Cops have recovered $180,000 in cash and 2 KILOS of heroin.
18 arrests have been made in connection with the ring and face charges of conspiracy, operating a drug ring, drug possession and more.