An unidentified South Korean reserve soldier went on a shooting spree at a military training camp on Wednesday in Seoul, killing a fellow reservist and wounding three others, before committing suicide, according to army officials.

The soldier started shooting at his colleagues with a K-2 rifle during mandatory drills at a training site for reserve forces in Seoul. The shooter killed himself after the rampage. One of the injured soldiers was declared dead at a hospital, the Associated Press (AP) reported, citing army officials.

The reservist "opened fire on his colleagues while receiving training at a military camp in Naegok-dong, southern Seoul, at around 10:44 a.m. today," the South Korean army said in a statement, obtained by Yonhap news agency.

Shootings at military camps by South Korean soldiers have occurred frequently in recent years, raising concerns about harassment and mental health conditions in the country’s armed forces, the AP reported, adding that a reservist going on a shooting spree is, however, unusual.

In February, a South Korean soldier was sentenced to death by a military court for killing five of his colleagues in a shooting spree at a guard post near the border with North Korea last year. The 22-year-old sergeant, surnamed Lim, was accused of throwing a grenade and had opened fire on members of his unit, killing five and wounding seven.

Lim later told investigators that he opened fire on fellow soldiers after they made a drawing of him, which he considered insulting, the AP reported.

In 2011, a 19-year-old South Korean marine conscript killed four colleagues on a western island near the border. A similar incident in 2005 claimed the lives of eight soldiers when a conscript threw a grenade and shot at the sleeping men at a frontline guard post, the South China Morning Post reported.