Chikkala Vasudeva Rao (24) died on his way to hospital while Yandmuri Satish (27) sustained serious burn injuries in the mishap when they were loading boxes of firecrackers into a van from a nearby godown yesterday evening, they said.
Another staffer Srinivasa Rao escaped with minor injuries.
According to police, the explosion occurred after one of the boxes of firecrackers fell on ground.
A case of negligence has been registered against the owner of the facility and further investigations are on, police said.