The death of rapper O.D.B. was ruled an accident by New York City medical examiner's office who said Wednesday that he died from the combined effects of cocaine and a prescription painkiller.

O.D.B., whose legal name was Russell Jones, died at a Manhattan recording studio Nov. 13.

He died "as a result of intoxication by the combined effects of cocaine and Tramadol, a prescription painkiller but not a narcotic," said Ellen Borakove, a spokeswoman for the New York City medical examiner's office.

"The manner of death is an accident," she added.

O.D.B. complained of chest pains before collapsing at the studio, and was dead by the time paramedics reached him. He was just days short of his 36th birthday.

O.D.B., also known as Ol'' Dirty Bastard, was one of the founding members of the rap group the Wu-Tang Clan.