Record label Murder Inc, which is behind stars including Ja Rule and Ashanti, was funded by drug money, US investigators have reportedly been told.
Rap industry insiders told a federal money-laundering investigation that the label was launched with money from notorious New York drug lord Kenneth "Supreme" McGriff, according to a document obtained by the Associated Press news agency.
Ashanti is one of Murder Inc's most successful artists
Murder Inc, its chief executive Irv Gotti and other rap figures are under investigation, although neither Mr Gotti nor Mr McGriff have been charged.
Mr McGriff has also been linked to the shooting of rap star 50 Cent in 2000. He and Mr Gotti deny any wrongdoing.
Mr McGriff, who was sent to jail for 10 years in 1987, is currently awaiting sentencing after pleading guilty to a separate gun possession charge.
The details came from an affidavit signed by an agent from the Internal Revenue Service and recently made public, which seen by the Associated Press (AP).
It accuses Mr McGriff of laundering money by giving it to Murder Inc and being paid back under false names.
According to the affidavit, Mr McGriff used drug proceeds as "start-up money" for the label in the late 1990s.
50 Cent survived being shot nine times in 2000
One unnamed informant told investigators that while "Gotti is the public face of Murder Inc, McGriff is the true owner of the company," AP said.
"It is well-known in the music industry that McGriff has provided Murder Inc with 'muscle'," it said.
Informants also linked McGriff to acts of violence "including the shooting of a rap artist named 50 Cent who wrote a song exposing his criminal activities".
50 Cent, the biggest-selling star in the US so far this year, survived being shot nine times in 2000.
Several of his songs refers to "Supreme" McGriff and his "Supreme Team" gang.
Mr McGriff's lawyer, Robert M Simels, described the allegations as groundless.
The affidavit contained "lots of allegations but at this point apparently not enough proof to charge anybody with anything", he told the Washington Post.
The FBI led raids on Murder Inc's offices in January, seizing records and computer drives.