Thai police say they would welcome the FBI's assistance in investigating the death of actor David Carradine, but only as observers, as mandated by Thai law.
A top Thai police official says they "have nothing to hide."
Carradine's naked body was discovered last Thursday morning in his luxury suite at a Bangkok hotel.
Police initially suspected his death was a suicide, but have since said it may have been accidental suffocation or heart failure.
He was found with a rope tied around his wrist, neck and genitals. A prominent Thai forensic pathologist says the circumstances suggests he might have died from a dangerous form of sex play.
Carradine's family wants the FBI to help investigate the case.
An FBI spokeswoman has said the agency generally only gets involved in death investigations overseas if a crime is suspected.