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Police Lt. Gen. Worapong Chewprecha told reporters that Carradine was found with a rope "tied around his penis and another rope around his neck," according to the Associated Press. "The two ropes were tied together," Chewprecha said. "It is unclear whether he committed suicide or not or he died of suffocation or heart failure due to an orgasm."
The Associated Press reports that authorities in Thailand ordered an autopsy on Carradine's remains. The autopsy was completed, but the results were not yet released.
Thai police say Carradine appeared to have hanged himself. The lead investigator has confirmed that they found "his body, naked, hanging in the closet."
When Eyewitness News broke the story Thursday morning, Chuck Binder, Carradine's manager, had said he believed the actor died of natural causes.
But Thai police suspect Carradine committed suicide. Authorities say Carradine died either late Wednesday night or early Thursday.
The Web site of the Thai newspaper The Nation said Carradine didn't show up for a meal with the rest of the film's crew on Wednesday night, and that his body was found by a maid Thursday morning. The Nation also reports that a preliminary police investigation found that he had hanged himself with a cord used with the room's curtains.
The actor reportedly had been staying at the luxury Swissotel Nai Lert Park Hotel.
He was born John Arthur Carradine, the eldest son of actor John Carradine.
Carradine's family is full of actors, including his father, a stage actor, and his three brothers, Keith, Robert and Bruce, screen actors. His neice, Martha Plimpton, is an actress.
Carradine was open about his past personal excesses, including hard drinkning and using drugs. He claimed in a 2004 interview that he had reduced his vices to coffee and cigarettes.
Carradine wrote in his 1995 autobiography, "Endless Highway," that he had tried to hang himself at age 5. His father saved him after he jumped off of the family car with a noose around his neck.
The Associated Press contributed to this report.
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