Two men have been indicted in the 2002 slaying of hip-hop artist Jam Master Jay, which until now had been one of New York City's - and United States music’s - most notorious unsolved killing.

Jam Master Jay, the DJ for hip-hop group Run-DMC whose real name was Jason Mizell, was killed inside a recording studio in the New York City borough of Queens on October 30.

Mizell was shot once in the head with a .40-caliber bullet by a masked assailant at his studio in Hollis, the Queens neighbourhood where he grew up, police said at the time.

The US Attorney's office for the Eastern District of New York said in a news release on Monday that Karl Jordan Jr would be arraigned later on Monday on charges of murdering Mizell, while Ronald Washington would be arraigned later this week.

Washington, who had reportedly been living on a couch at Mizell’s home in the days before his death, was publicly named as a possible suspect or witness as far back as 2007.

He is currently serving a federal prison sentence stemming from a string of robberies he committed while on the run from police after Mizell’s killing.

Washington had also been linked to the 1995 fatal shooting of Randy Walker, a close associate of the late Tupac Shakur.

Police identified at least four people in the studio with Mizell at the time of the killing, including the two armed gunmen.

The city and Mizell's friends offered more than $60,000 in reward money, but witnesses refused to come forward and the case languished

Run-DMC, one of the best-known rap acts of the 1980s, was founded in New York City in 1981.