An ambulance enters the Army's 32nd Infantry Division in Sejong, 113 kilometers south of Seoul, on Tuesday. (Yonhap)

A violation of military regulation occurred with a recent trainee soldier's death during a training exercise, an Army official told local media Monday.

In a meeting with reporters, the unnamed official confirmed that there "had been a situation that was not in accordance with (military) regulation" during the exercise. The official refused to elaborate, saying the case was still under investigation by the police and the military.

According to the Army, the trainee soldier died Saturday while being treated at a civilian hospital, two days after collapsing at a unit in Inje, Gangwon Province, at around 5:20 p.m. on Thursday.

The deceased had been carrying out a training exercise that is not part of the regular program, conducted usually as a disciplinary action when the commander deems it necessary. A total of six soldiers took part in the said training, which involved them running laps around the grounds while fully equipped with their gear.

The non-government Center for Military Human Rights Korea on Monday called for a thorough investigation of the incident, claiming that the training exercise was conducted without regard for the physical conditions of the deceased soldier. Citing an anonymous tip, it claimed that the six soldiers were ordered to run laps because they made noise at night.

It also claimed that the military official on the site had been aware of the deceased soldier's condition, but brushed it off as faking illness.

The Army official who addressed the media Monday did not confirm or deny the claims, simply saying the military and the police will verify the events through investigation.

The incident sparked widespread criticism of the military and its treatment of soldiers, who are conscripted soldiers completing their mandatory military duty. South Korea mandates all able-bodied men to serve in the military for at least 18 months.

Just days before the incident, another trainee soldier died Tuesday in a grenade explosion during a training session at the Army's 32nd Infantry Division.

Cho Kuk, the leader of the minor opposition Rebuilding Korea Party, wrote on his Facebook page that there needs to be a system protecting the human rights of conscripted soldiers and compensating those whose rights have been violated.