THANE, India (AP) — An explosion and fire at a chemical factory in western India killed at least nine people and 64 were injured, officials said Friday.

The explosion Thursday in the factory’s boiler led to a fire that affected nearby factories and houses in Maharashtra state’s Thane district, administrative official Sachin Sejal told news agency Press Trust of India.

Sejal said the blaze has been extinguished but rescuers were expecting to find more bodies in the debris.

The cause of the explosion, which sent a huge cloud of grey smoke over the area, is being investigated.

The factory produced food coloring and used highly reactive chemicals that can cause explosions, India's National Disaster Response Force said.

Fires are common across India because of poor safety standards and lax enforcement of regulations. Activists say builders often cut corners on safety to save costs and have accused civic authorities of negligence and apathy.