A fact-finding committee of the chief of defence forces concluded that cadet Pakapong "Moei" Tanyakan died in October due to his weak health in contrary to his family's belief in assaults.
A military source said on Tuesday the panel concluded its probe Tuesday evening that the death resulted from a sudden cardiac arrest and weak health.
According to the source, the committee also found that Pakapong had frequently received treatment from the medical room at the Armed Forces Academies Preparatory School and once collapsed in a physical activity class.
The cadet had been in the medical room two days before his death. The probe result echoed the earlier conclusion of the cadet school, the source said.
The latest probe committee would report its findings to Defence Forces chief Thanchaiyan Srisuwan on Wednesday and a press conference on the issue was expected this week, the source said.
Earlier the family of Pakapong, 18, said an autopsy by the Justice Ministry's Central Institute of Forensic Science showed the bruises and a broken rib might have been caused by assaults.
Pakapong died on Oct 17, one day after he returned to the Armed Forces Academies Preparatory School after a short break.