At least 40 workers of a chemical factory were injured on Wednesday in a huge fire caused by a blast in the boiler at Dahej in Bharuch district of Gujarat, district collector said.

"Around 35-40 workers sustained burn injuries after the boiler of an agro-chemical company exploded in afternoon. All the injured persons have been shifted to hospitals in Bharuch, and efforts are on to control the fire," said Bharuch collector MD Modia.

The fire has still engulfed the unit, the collector said.

He said residents of Lakhi and Luvara villages located near the factory are being evacuated as a precautionary measure because of the presence of plants of poisonous chemicals near the affected factory.