BARABANKI: Two persons died while three others were injured in an explosion inside a licensed firecracker factory here on Thursday, with police suspecting that something inside the factory triggered the blast.

The incident occurred in Sarai Barai village of the Tikaitnagar area, triggering panic among locals.

Police said the explosion inside the factory led to a fire with thick plumes of smoke seen rising from the factory.

Superintendent of Police (SP) Arpit Vijayvargiya said fire tenders were rushed to the spot upon receiving information. "The factory was operating with a valid licence to manufacture firecrackers. Preliminary investigation suggests that something inside the premises triggered the blast," the officer said.

Police have sealed the site and called in a forensic team to collect evidence. Efforts are on to clear the debris and search for anyone who might still be trapped inside, he added.

Three persons with critical burn injuries have been admitted to a hospital. After the initial explosion, several firecrackers continued to go off for some time, police said.