Kolkata, Dec 1 (IANS): Three persons were killed and several others injured in a huge blast at a residential building in South 24 Parganas district's Mohanpur village on Wednesday morning, police said.

According to the police, the owner of the house had stacked huge amounts of illegal explosives possibly for making firecrackers which resulted in the blast. The owner of the house -- Ashim Mondal and two of his employees -- were killed in the blast.

According to the local people, Mondal had been running an illegal firecracker factory in the locality for the last ten years. "This is a residential area and we had the fear that this kind of explosion could take place. We requested him several times and also informed the police, but nothing happened," a local resident said.

According to the local people, the magnitude of the blast was so high that the window panes of some of the neighbouring houses broke and the bodies were thrown nearly 200 metres away from the blast site. According to the police, the blast took place on the roof and the concrete roof collapsed.

"The bodies have been sent for post-mortem and we have informed the forensic team. Once they give their report we will be able to understand the nature of the explosives and the exact location of the blast," a senior police officer said.