The helicopter, from Thap Phraya Sua Camp in Ratchaburi's Suan Phung district, crashed into a mountain in a bad weather Saturday while on a mission to remove civilians who had been trapped in Kaeng Krachan National Park, the Bangkok Post reported.
Military troops were sent to the area to recover the crash victims' bodies.
The dead soldiers are: Maj. Kitisak Chin-iam, first pilot; Lt. Pratya Nualsri, second pilot; Maj. Kitiphum Ekkaphan, deputy commander of the 2nd Infantry Battalion of the 9th Infantry Regiment; and two mechanics, Sgt. Maj. Rangsan Polsaibua and Sgt. Maj. Narongdet Pongnumkul.
It was unclear if the helicopter had already picked up the civilians when it went down. The report didn't say if any civilians died in the crash.