NEW YORK (AP) _ A year has passed since a gunman clad in black walked into the Queens recording studio of Jam Master Jay and _ possibly after greeting the rap legend with a hug _ pumped a bullet into his head.

Since then, police say they have pursued ``several significant leads,'' including some that suggest the rap legend died in a dispute over money. But Thursday's anniversary of a slaying that shook the music industry appeared likely to pass with the killer still at large.

Homicide detectives in Queens _ where the pre-eminent DJ and founding member of Run-DMC was killed on Oct. 30, 2002 _ say the case remains a top priority. They deny reports their hunt for the gunman has stalled.

``It's a very active investigation,'' Deputy Chief Michael Collins, a police spokesman, said Wednesday. ``We're pursuing several significant leads.''

The city, music industry notables and family members have helped keep the killing in the headlines by offering tens of thousands of dollars in rewards. Hip hop luminaries such as Russell Simmons and Sean ``P. Diddy'' Combs have been invited to mark the anniversary at a memorial service Thursday night near the murder scene in Queens.

But privately, investigators have complained that some witnesses have been uncooperative. And with no major breaks, the case has drawn comparisons to the unsolved slayings of rap superstars Tupac Shakur in Las Vegas and Notorious B.I.G. in Los Angeles.

The 37-year-old victim, whose real name was Jason Mizell, spent his last moments lounging in his 24/7 Recording Studio the night of his death.

The DJ had gained fame working the turntables as Russell Simmons' brother, Joe ``Run'' Simmons, and Darryl ``DMC'' McDaniels rapped on hits like ``King of Rock,'' ``It's Tricky,'' and a Top 40 remake of Aerosmith's ``Walk This Way.'' In more recent years, he had helped produce and promote lesser-known artists.

Witnesses said a large man wearing a black sweat suit and black hat appeared inside the studio and, according to a report in Newsday, embraced Mizell. He then pulled out a .40-caliber pistol and opened fire.

A first round missed Mizell, instead injuring a performer who was working in the studio. A second bullet, this time fired from point-blank range, entered the left side of Mizell's head. The shooter vanished.

To detectives, a hug would suggest Mizell knew his killer. But the identity of the shooter _ and his motive _ have been the subject of conflicting reports.

There has been speculation that Mizell, who was drowning in debt, may have been killed on orders from someone he owed money. Other reports have suggested that the victim was involved in drug deal gone bad.

Some authorities also have suggested Mizell was caught in the crossfire of a rivalry between rap figures who associate with known criminals. 50 Cent _ a Queens-reared rapper who worked with Mizell _ has feuded with Irv Gotti, head of the Murder Inc. recording label.

Federal agents earlier this year raided the Manhattan offices of Murder Inc. amid allegations that the label was laundering money supplied by a convicted drug kingpin, Kenneth McGriff. Prosecutors believe McGriff may know something about Mizell's death.

Gotti and McGriff have denied any wrongdoing.