At least 11 Bhutanese soldiers were killed in an explosion on Monday while disposing of old ordnance, news reports said.
The incident occurred near a military base in Anakha in the western district of Haa, according to the Twitter account of the state-run Kuensel newspaper.
Eight soldiers died on the spot and three more succumbed to injuries in hospital, the report said.
About a dozen more soldiers were hospitalised with injuries. The rest of the ammunition would now be sorted by hand to prevent further explosions, the report said.