Accidents during military training exercises are not entirely unheard of. Many soldiers have lost their lives in such accidents in the past.

In yet another incident, four Indonesian soldiers were killed on Wednesday (17 May) when an artillery cannon blew up during a training exercise on a South China Sea island.

The training exercise, held on an island on the small Natuna archipelago in the South China Sea, was reportedly aimed at bolstering maritime defences to protect Indonesia's special economic zone from perceived Chinese aggression amid frequent clashes between the two countries' vessels.

Eight other soldiers were injured in the accident, four of whom suffered serious injuries, army spokesman Alfret Denny Tuejeh told Agence France Presse on Thursday.

"The cannon became uncontrollable and hit soldiers in the vicinity," the spokesman added, noting that the same cannon used a day before worked without any problem. An investigation has been launched to establish the cause of the accident, he said.

A similar training accident that resulted in the death of a female US Army combat photographer and four other soldiers was recently reported and photographs of her last moments were released.

The incident took place in Afghanistan's Laghman Province on 2 July, 2013 during a mortar training exercise involving soldiers of the Afghanistan National Army First Cavalry Division. Spc Hilda Clayton, 21, was documenting the training exercise and captured the moments just before the explosion ended her and the others' lives.