QUEENS, NY (10.20.03)--After a year with no arrests in the murder of Jam Master Jay, friends and family of the hip-hop icon are taking matters into their own hands, launching their own investigation and offering $500,000 to shake loose clues.

Frustrated with the pace of a probe that has generated more rumors than leads, associates of the legendary record-spinner - whose real name was Jason Mizell - said they would hire a private investigator to assist cops who have run into a wall thicker than the one on 205th Street in Hollis, Queens, where a mural was painted in the slain deejay's honor.

"Any help we can get to solve this case is welcome," Mizell's brother, Marvin Thompson said.

"I don't want this to just go away unsolved like Tupac and Biggie's cases. I want a closure to this case, and I think the people want some closure to this case as well."

Rival rap stars Tupac Shakur and Biggie Smalls were murdered six months apart. After more than six years, their murders remain unsolved.

Mizell, 37, the track-mixing pioneer behind rap group Run-DMC, was shot to death by a masked gunman last Oct. 30 in the lounge of his Jamaica, Queens, recording studio, triggering what some have called a new rap war and a struggle for control of the hip hop music industry.