Dead at the scene were Chayakorn Phutchaiyong, 19, and Nattawut Tirasuwannasuk, 21.
“I am told the accident stemmed from static-line problems,” Royal Police Cadet Academy commander Lt-General Sakda Techakriangkrai said.
He vowed to investigate the cause of the accident further.
Witnesses said the victims were among the first lot of people to jump out of the aircraft, which was about 1km above the ground at the Rama VI camp.
Among the witnesses were Chayakorn’s parents.
“I saw a body dropping down onto the ground but at first I didn’t think that it’s my son’s. When I rushed to the body and found who the victim was, my heart broke,” Chayakorn’s father Satorn Phutchaiyong said.
“I want to find out why my son’s parachute was not working”.
National Police Commissioner General Adul Saengsingkaew said he would seek a royal-granted fire for the victims’ cremation ceremonies.