The father of actor Woody Harrelson died of an apparent heart attack as he slept in his super-maximum security federal prison cell in Colorado, officials said.

ADVERTISEMENT

Fremont County (Colo.) Coroner Dorothy Twellman said an autopsy showed Charles Harrelson had severe coronary artery disease and probably died while asleep, the Denver Post reported Wednesday.

"It appears it was very sudden," Twellman said.

Bureau of Prisons spokeswoman Felicia Ponce said Harrelson, 69, was unresponsive when guards checked on him last Thursday.

Harrelson was transferred to the Florence, Colo., prison in 1994 after allegedly trying to escape from a federal prison in Atlanta.

He was convicted of killing federal Judge John Wood in San Antonio in 1979. Prosecutors said he was paid $250,000 by drug dealers who wanted to avoid appearing before Wood. Harrelson claimed he was 270 miles away from the scene at the time.

Woody Harrelson was 7 when his father went to prison for killing a businessmen and in college when his dad was convicted in the judge's death.

Harrelson played a bartender in the TV sitcom "Cheers," then starred in films such as "White Men Can't Jump" and "Natural Born Killers."