A member of Japan's Self-Defense Forces (SDF) died on Thursday over a hand grenade explosion during a training session in Yamanashi Prefecture, according to local media reports.

The accident took place around 8:45 a.m. local time at the Ground Self-Defense Force's (GSDF) training ground, Kitafuji Exercise Area, where a 29-year-old male soldier taking part in the training was hit by shrapnel from a hand grenade thrown by another SDF member.

The injured was rushed to a hospital unconscious but confirmed dead about two hours later, and the GSDF is investigating the cause of the incident, national news agency Kyodo reported.