The plane, carrying 108 soldiers, their family members and 14 crew members, was traveling to Yangon, Myanmar's largest city, from the southern coastal town of Myeik on Wednesday afternoon before contact with the aircraft was lost.
Three bodies belonging to two adults and a child were found 35 kilometers from the southern coastal town of Launglon.
"We found the plane and some dead bodies this morning at about 8:25 a.m. (0155 GMT)," a military spokesman told the media.
Nine naval vessels, five aircraft and two helicopters of the Air Force as well as local vessels are continuing the search operation, the spokesman said.