At least seven people were killed and seven others injured Sunday in a massive explosion at a firecracker factory in India's northern state of Uttar Pradesh, police said.

The blast took place at Maheva village in Kaushambi district, about 169 km south of Lucknow, the capital city of Uttar Pradesh.

According to police, the victims were among the around 18 people working in the factory when the blast took place, which was heard several kilometers away.

The blast also triggered a blaze in the factory.

"Today an explosion took place at a firecracker factory here killing seven people, including the owner, and injuring seven others," a police official said. "The blast occurred in the room where chemicals were kept."

Accidental explosions are common at Indian firecracker factories and shops as owners usually ignore safety standards.

xinhua