A hand grenade explosion killed one recruit and severely wounded a noncommissioned officer during a training session held at an Army boot camp in the administrative city of Sejong, officials said Tuesday.

“Around 9:50 a.m. on Tuesday, an accident involving a hand grenade explosion occurred during grenade throwing training at (the Army's 32nd Infantry Division) in South Chungcheong Province,” the Republic of Korea Army said in a statement released via text message to reporters.

“The wounded soldiers were immediately sent to the Armed Forces Daejeon Hospital, but the recruit has unfortunately passed away, while the officer is currently conscious and receiving emergency medical care,” it added.

The recruit, in a state of cardiac arrest, was sent to the nearby hospital in the city of Daejeon, located just south of Sejong, but was soon pronounced dead. The officer, whose hand and arm were severely wounded, was transported to another military hospital.

The exact cause of the incident is currently unknown, but a military official told reporters that they suspect the explosion occurred unexpectedly as the recruit removed the safety pin from the grenade. The Army pledged to cooperate with the police in probing the cause of the explosion and expressed condolences to the bereaved family of the dead recruit.

This marks the seventh time that a hand grenade explosion during military boot camp training here has led to casualties, with the first of its kind having occurred in 1994.

In 2015, one army sergeant was killed and two recruits were wounded due to a hand grenade explosion during an Army boot camp training session in the southern city of Daegu.

The National Assembly’s National Defense Committee later found that the Army continued to use the “K413” grenade designed and manufactured by Hanwha Corp., regardless of the Republic of Korea Army Ammunition Support Command’s earlier assessment that deemed the product’s design as “flawed.”

The Army explained that they had used the same design, but the manufactured year and the production line of the exploded grenade were different from the ones that the Ammunition Support Command had unapproved.