JAIPUR, India - Firefighters in northern India struggled Friday to douse a gigantic blaze burning for more than 12 hours at a major oil depot, where at last three people were killed and scores injured.

After burning throughout the night, the Indian Oil Corp. facility on the outskirts of Jaipur in the desert state of Rajasthan was still engulfed by huge flames and black smoke.

Indian Oil Minister Murli Deora told reporters that there was little the firefighters could do but try to contain the blaze, suspected to have been caused by a leak on a pipeline.

"You cannot stop the fire. All the fuel in there has to burn out before we can reach there... when there is such a huge fire all safety measures prove inadequate," he said.

Jaipur's chief civil administrator, Kiran Soni Gupta, said three people had died in the blaze that caused emergency service officials to evacuate thousands of people living nearby.

At least 80 people were admitted to local hospitals with burn injuries, Gupta added.

The Press Trust of India reported five killed and 150 injured in the fire, which engulfed four oil storage units at the depot covering an area of several square kilometres (miles).

Rajasthan police chief Harish Meena told reporters late Thursday that an "oil leak in a pipeline" appeared to have been the cause.

Local residents reported hearing a large explosion as the blaze broke out.