
The US Embassy in Bangkok facilitated the transfer of his body which left Suvarnabhumi Airport in a United Airline flight at about 7pm.
The 72-year-old actor was found dead inside his suite at the Swissotel Nai Lert Park hotel on Thursday. His body was naked and his sexual organ was tied by a rope. There was no trace of a fight or struggle at the scene.
Police have yet to determine how Carradine died.
An accident during an attempted auto-erotic asphyxiation is now cited as a possible cause of death.
During an auto-erotic asphyxiation, practitioners achieve heightened sexual pleasure by restricting their air supply.
"Circumstances in which he died point to an auto-erotic asphyxiation," Central Forensic Science Institute director Khunying Porntip Rojanasunand said yesterday, "But this is just an assumption. We have to look at other circumstantial evidence and witnesses too".
Police have not yet ruled out murder in Carradine's case.
It may take four more weeks to determine the exact cause of his death.
Lumpini Police Station superintendent Colonel Somprasong Yentuam said relevant officials had been checking all fingerprints found in Carradine's suite.
"They are also checking whether there were toxic substances inside his body," Somprasong said.
He expected the Scientific Crime Detection Division to submit test results in a week.
Chulalongkorn Hospital forensic doctors may need three weeks to complete their task in the case.
"At this point, we have yet to obtain any more clues. The star's friends and colleagues do not think he was murdered," Metropolitan Police Commissioner Lt-General Worapong Chiewpreecha said yesterday.
Carradine's personal manager, Chuck Binder, also dismissed any suggestion that the famous actor - who starred in "Kung Fu" and "Kill Bill" - committed suicide.
"We can confirm 100 per cent that he never would have committed suicide," he said.
Somprasong said the US Embassy in Bangkok did not question the cause of death.
However, the embassy has questioned what they called "a violation of privacy", as the Thai media was informed of the details relating to the star's death.
"But we are not the one who broke the news," Somprasong said.
Aurelio Giraudo, general manager of the hotel, said in a statement that Thai police had confirmed the death of US actor.
According to the hotel, its focus is to assist the police in their investigations.
"We are not in a position to discuss any details of this case nor disclose any other information," said Giraudo.
Since Carradine's death appeared on news headlines, condolences came pouring in to the actor's website www.davidcarradine.com.
"What a sad day it is for all who grew up watching David Carradine and knowing this great actor. May you rest in eternal peace," said one post.