A former U.S. Marine has admitted to killing a young woman whose body was found in bushes beside a road in central Okinawa, investigative sources said Friday.

Kenneth Franklin Shinzato, 32, told police on Thursday that he strangled and stabbed 20-year-old Rina Shimabukuro, an office worker from Uruma, the sources said. He was arrested on suspicion of dumping the victim's body, a procedural step common in suspected murder cases.

An autopsy was unable to confirm the cause of death, police said Friday.