The intensity of the fire was so high that people in the villages around were woken up to a loud noise, with their houses shaking.
Around 10 to 15 contract labourers were at the site when the incident occurred, Wardha's additional superintendent of police Nikhil Pingle said.
The intensity of fire and explosions at central ammunition depot at Pulgaon in Wardha district was such that seven of the victims were blown to pieces, a top police official said.