A military inquiry has concluded that Royal Thai Armed Forces Academies Preparatory School cadet Pakapong Tanyakan died of acute heart failure, with no evidence of physical abuse.

The mother of 18-year-old cadet Pakapong "Moei" Tanyakan has attacked the Royal Thai Armed Forces (RTAF), accusing them of blaming her son for the events leading up to his death.

Bangkok (AFP) - Thailand's military on Friday cleared itself of responsibility for the murky death of an 18-year-old cadet following its probe into a case that has become a lightning rod for anger over abuse of young recruits in the kingdom's barracks.

A military-run committee probing the mysterious death of 18-year-old cadet Pakapong "Moei" Tanyakan, has concluded it was caused by sudden heart failure, not assault, according to a source.

The mother of 18-year-old cadet Pakapong "Moei" Tanyakan has vowed to seek justice for her son following reports that a military-appointed committee probing his mysterious death has concluded it was not caused by assault.

The Tanyakan family who lost their young son under mysterious circumstances in October while he was studying at the Armed Forces Academies Preparatory School is taking the armed forces to task for an investigation into the case they described as "a disappointment". They have every right to do so.