MUAN, South Korea: South Korean authorities began releasing the bodies of plane crash victims to families on Tuesday (Dec 31), as investigators raced to determine why the Jeju Air Boeing 737-800 crash-landed and burst into flames. US investigators, including from Boeing, arrived at the crash site in southwestern Muan, officials said, as South Korean authorities began assessing two black boxes retrieved from the burned-out wreckage of the aircraft. The plane was carrying 181 people from Thailand