Ozzy Osbourne's cause of death has been revealed. The Black Sabbath rocker died at age 76 from a heart attack, according to his death certificate obtained by The New York Times and The Sun. The death certificate reportedly listed Osbourne's cause of death as "out of hospital cardiac arrest,

Ozzy Osbourne's official cause of death has reportedly been revealed two weeks after the rock legend died in Birminghamshire, England on July 22.

Legendary Black Sabbath frontman Ozzy Osbourne 's cause of death was a heart attack, his death certificate shows. The heavy metal icon died on July 22 at age 76, at Harefield Hospital in the United Kingdom.