David Carradine did not commit suicide, a second autopsy concluded Thursday, the Associated Press reports.
Still, the forensics expert hired by the late Kung Fu actor's family said that more information was needed from Thai investigators to determine the true cause of death.
"To reach a final determination as to the cause and the manner of death, we must wait for further information from Thailand as to the scene findings and the completion of the crime laboratory and toxicology studies that are still being performed," Dr. Michael Baden said in a statement.
Baden said he expects to receive more information from Thai authorities in a week or two and stressed that the information at hand was incomplete. "The autopsy is only part of the analysis," he said.
In their first appearance since their older brother was found hanging in a closet inside his Bangkok hotel room last week, Keith and Robert Carradine discussed the results with reporters in L.A. on Thursday morning.
"Until we have all of the pending results of the investigation we respectfully ask ... that we be allowed to lay our beloved brother, husband, father, grandfather and great-grandfather to rest in peace and with dignity," Robert Carradine said. "Once the investigation is fully completed and definitive conclusions have been reached, we will address the findings with the public."
Although police initially believed the Kill Bill star, 72, committed suicide, they later said it could have been accidental. Their description -- that the actor's body was found nude, with ropes around his neck, wrist and genitals -- of the June 4 crime scene fueled speculation that he was killed while engaging in a dangerous sex practice called auto-erotic asphyxiation. Still, others have suspected foul play.
"This is a devastating loss for our family, and we greatly appreciate the compassion pouring in from all over the world," Keith Carradine said.