A two-storey building in Howrah’s Uluberia was rocked by an explosion Sunday morning.

Police said illegal firecrackers stockpiled inside the house had exploded. No one was trapped or injured.

Neighbours at Tantiberia village in Uluberia, around 42km from the heart of Calcutta, said they heard a loud sound early on Sunday.

The windowpanes on the first floor were smashed and some of the walls developed deep cracks under the impact of the blast.

“The buildings near the one where the explosion occurred shook under the impact and their windowpanes cracked,” said a villager.

The owner of the house, Shyamal Mandal, runs a business selling electrical goods and some electrical gadget or a battery might have exploded, a family member reportedly told the police.

“My brother is in the business of selling electrical gadgets. He deals with a lot of batteries. Many batteries were stored on the first floor. The fire might have started from there. I am not aware of any illegal firecrackers stored in the house,” a police officer quoted Mandal’s brother Amalendu as having told them.

The police, however, said the explosion was caused by firecrackers. “Manufacturing and stockpiling firecrackers at home is illegal,” said anofficer.