US singer-songwriter Isaac Hayes has died at his home in Memphis, Tennessee, at the age of 65, police said.
Police were called to Mr Hayes' home after his wife found him unconscious. He was taken to hospital where he was pronounced dead at 1408 (1908 GMT).
Mr Hayes, a flamboyant, deep-voiced performer, won an Oscar for the 1971 hit Theme From Shaft.
He was perhaps better known to a younger audience as the voice of Chef from the hit cartoon show, South Park.
The cause of death was not immediately known.
"Family members believe at this point it is a medical condition that might have led to his death," a police spokesman said, adding Mr Hayes was being treated for "a number of medical issues".
Mr Hayes suffered a stroke in 2006.
Hayes the showman
Isaac Hayes - along with Al Green, James Brown and Stevie Wonder - was one of the dominant black artists of the early 1970s.
Hayes was renown for his deep voice and flamboyant on-stage style
Hayes, a self-taught musician, was hired in 1964 by Stax Records as a back-up pianist and saxophone, working as a session musician for big names such as Otis Redding.
He established a songwriting partnership with David Porter, and in the 1960s, writing hits for Sam and Dave such as Hold On, I'm Coming and Soul Man. This success led on to a recording contract, and in 1969 he shot to fame with the release the groundbreaking album Hot Buttered Soul.
The them from the film Shaft was a number one hit in 1971. He won an Academy Award for the song and was nominated for another one for the score. The song and score also won him two Grammys.
Isaac Hayes was also in several movies, including It Could Happen to You with Nicolas Cage, and Ninth Street with Martin Sheen.
He had success later in life as the voice of the South Park character, Chef. But he angrily quit the show in 2006 after an episode mocked Scientology, a religious movement to which he belonged.
He was married four times and has 12 children.
another death in the entertainment world.