Three persons died in an explosion in a boiler of a brick kiln on the highway at Jodimetla under Ghatkesar police station limits on Saturday night.
The deceased were supervisor Anji Reddy (45), boiler operator Narsimha (45) and security guard Bahadur Singh (50).
Police said the blast could have occurred due to excessive pressure in the boiler. Police said a case would be booked against the manufacturer after collecting details from the mishap site on Sunday. Another worker Yadagiri sustained injuries.