
Lumpini police are investigating Carradine's death to determine the cause.
Carradine's family has asked the FBI to help investigate his death.
Somprasong said the film crew manager had told police they would give testimony next week and that police had not yet concluded if the 72-year-old actor had committed suicide or been murdered, pending forensic investigation results.
Asked about the deceased's relatives' comment that they did not believe it was suicide and would ask the FBI to jointly investigate the case, Somprasong said he had not yet been told of such a move and police would do as their superiors decided. He said that if the FBI wanted to come in, he personally would be willing to cooperate to solve the mystery.
Carradine was found dead inside his suite at the Swissotel Nai Lert Park hotel on Thursday, and there was no trace of a fight or struggle.