Two army men are also said to have been injured in the incident.
A court of inquiry has been ordered to investigate the incident by the Indian army.
Bomb explosion
The incident is said to have happened due to explosion of a bomb inside the barrel leading to bursting of the barrel, army spokesperson Col N N Joshi has said from Jodhpur.
The unfortunate incident happened on Wednesday, approximately around 2 pm, he said.
Though he confirmed the casualties, he said the details of the unfortunate accident were still awaited.
The explosion took place in Pokhran, during the field firing exercise, where Operation Brazen Chariot was held to showcase the joint combat prowess of the Indian army as well as the Indian Air Force, engaging the latest array of weaponry in a joint air-land exercise.
