Birbhum police have started a probe into a blast that injured a visitor inside the Dubrajpur police station on August 10.

Police sources said the injured had been admitted to a private hospital and was undergoing treatment.

Senior police officers said the explosion had taken place on August 10 morning, but they came to know about it late as it had not been reported immediately. “We came to know about an explosion inside the Dubrajpur police station. We are investigating the case to find out what actually happened there,” said Shyam Singh, district police chief.

The sources said the explosion had taken place inside an almirah at the officers’ room.

“We don’t keep any explosive in almirah and all seized items are stored at malkhana. We suspect a battery or condenser of a ceiling fan exploded,” said a police officer in Dubrajpur.

The sources claimed it was an old building and the electrical wiring was also old.