Two Army privates who were on the military's list of soldiers "requiring extra care" have died after apparent suicides, the Army said Monday, sounding an alarm for the country's troop management.

A 21-year-old private, identified only by his surname Park, was found hanged in a restroom of his barracks in the central part of the country at about 8:10 p.m. on Sunday. He was immediately taken to a military hospital, but was pronounced dead some three hours later.

"After joining his unit on June 20, he showed a symptom of depression and had been on medication for about two weeks," an Army officer said, requesting anonymity. "He was categorized as a Class-A soldier who needs special attention."

As part of efforts to better manage the troops, the military conducts personality tests on draftees, and classifies into three categories those considered requiring extra care, considering their relatively unstable mental status and family backgrounds, among other factors, with Class-A soldiers being the most vulnerable.

A probe into the private's death is under way, including whether he had been abused by his colleagues, including physical assaults, according to the officer.

Also on Sunday, another Army private, surnamed Shin, was found hanged at about 4:35 p.m. in a restroom of his frontline unit in Goseong, about 250 kilometers east of Seoul, according to the Army officer. He died while being transferred to a nearby hospital.

He joined the Army in May, and was dispatched to the 22nd Infantry Unit earlier this month. Officers say he was also on the list of Class-A soldiers.

"He changed his position three times since joining the unit,"

the officer said, without elaborating further on the reasons for the frequent transfers. "No suicide note was found, and we are looking into the cause of his suicide."

Following a series of tragic incidents among the enlisted soldiers on the special attention list, there has been growing skepticism about the effectiveness of the policy and even criticism of its side effects.

Last month, an Army sergeant who was also on the list went on a shooting spree at his 22nd Infantry Division, killing five and wounding seven others.

The sergeant, who was stationed at the unit near the tensely-guarded inter-Korean border, had also been one of the Class-A soldiers, which had banned him from frontline duties, but was later classified as Class-B, which meant he still required special attention but was capable of carrying out normal duties.  

"It is literally impossible for us to prevent such vulnerable people from joining the Army. We've seen an increasing number of soldiers who need extra care, but few measures exist to help them adapt to military life," a defense ministry official said.

"We are struggling to find fundamental solutions amid the harsh reality of a lack of systematic measures to support the servicepersons and a reduction in the number of potential draftees due to the country's low birthrate," he added.

Because of the country's rapidly aging population, the government has lowered the bar for service in recent decades, with more than 90 percent of potential draftees ordered to serve.

All able-bodied South Korean men must fulfill mandatory military service for about two years to deter aggression by North Korea. (Yonhap)