A releative discovered an unresponsive Hayes near an exercise machine in their home at midday, and Hayes was pronounced dead at 2:10 p.m. when he arrived at Baptist East Hospital in Memphis, the Shelby County Sheriff's Office tells PEOPLE.
"The family had last seen him about noon," says Steve Shular, public information officer for that office. "Family members had gone to the grocery store and left him home. When the family came home around 1, his wife's cousin found him lying on the floor in the basement near a treadmill. The treadmill was running, so it is believed that he had been working out."
Although the hospital is still determining the cause of death, Shular says Hayes most likely died of natural causes.
"There doesn't seem to be any foul play," says Shular. "We don't see anything suspicious about his death. There will be a further statement from the hospital about the cause of death."
Family members said the singer, who had a history of high blood pressure, had recently been treated for various medical conditions. In January 2006, news sources reported that Hayes had suffered a mild stroke. At the time, friends said the condition was brought on by exhaustion.
South Park FavoriteWith his distinct basso profundo (his voice seemed emanate in his feet), from 1997 to 2006, Hayes voiced the role of South Park's school-cafeteria sage, Chef. However, he abruptly quit over what he considered the show's disrespect for religion.
South Park creators Trey Parker and Matt Stone speculated that Hayes was offended by the show's treatment of his faith, Scientology.
Born in Covington, Tenn., Hayes was a self-taught musician. At age 22, he was hired by Stax Records of Memphis to play backup for piano and sax for Otis Redding and others. In the '60s, with David Porter, he wrote soul hits for Sam and Dave ("Hold On, I'm Coming" and "Soul Man"), the Associated Press reports.
Rock Hall of FamerThis led to a recording contract, and by the early '70s he was working with chart-topper Barry White. Hayes struck gold with the "Theme from Shaft," by which time he had been a music star for two years – ever since the release of his 1969 album Hot Buttered Soul.
In terms of further distinctions, his Best Original Song Oscar for Shaft made him the first African-American songwriter to nab the coveted award. He was also elected to the Rock and Roll Hall of Fame in 2002.
As an actor, Hayes played the title character in the 1974 action film Hot Truck Turner, 2005’s Hustle & Flow (starring Terrence Howard) and had a recurring role on the 1970s TV police drama The Rockford Files, starring James Garner. He is also set to appear in a small part in the movie Soul Men, a comedy led by Samuel L. Jackson and the late Bernie Mac.
Family ManIn 2006, Hayes's welcomed a son, who was named Nana Kwadjo Hayes. It was the musician's first child with his wife Adjowa. (They were married in 2005.)
Hayes reportedly had 12 children, 14 grandchildren and three great-grandchildren.
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