Several people are feared trapped after a fire broke out at a factory in Thane’s Dombiwali near Mumbai following a massive blast on Thursday. The fire occurred after a boiler inside the chemical factory located in MIDC Phase 2 exploded, officials said.

Witnesses reported hearing three blasts at the factory. According to locals, nearly 30 people have been rescued from the building so far.

Over 10 fire engines are at the spot along with ambulances. Officials estimate it would take over four hours to douse the fire.

So far, four people have been taken to the hospital.

“We are waiting for more people to be rescued. The workers on the day shift were inside the factory when the explosion occurred. It is not known how many people are stuck inside,” Dr Nikhil Patil said.

The impact of the blast shattered the windows of the houses nearby. The fire has spread to two other buildings including a car showroom.