The incident occurred this morning near the Indian Military Training Team (IMTRAT) centre at Haa. The injured personnel of the Royal Bhutan Army (RBA) were taken to the nearby IMTRAT hospital.
Some seriously injured persons were flown to Thimphu in helicopters, media reports said.
The dead and injured were members the bomb disposal squad of the RBA. Further details, such as the cause of the blast, were not immediately available.
The IMTRAT centre at Haa was set up in 1960. Two years later, India set up the Wangchuk Lo Dzong Military School at the centre to train personnel of the RBA and Royal Bodyguards.