NEW DELHI, Jan. 2 (Xinhua) -- Several people including firefighters were trapped inside a factory that collapsed Thursday during a devastating fire inside it in the Indian capital, officials said.

The fire broke out in west Delhi's Peera Garhi area.

According to officials, an explosion during the fire caused collapse of the factory structure, trapping people under the debris.

Authorities have rushed 35 fire tenders to the spot to contain the blaze.

"The firefighting operation is underway and we are trying to rescue the people stuck in the burning building," a police official said.

According to the fire department, they received a distress call about fire at 4:30 a.m. local time and since then have been trying to douse it.

Delhi Chief Minister Arvind Kejriwal said he was closely monitoring the situation.

"Very sad to hear this. I'm closely monitoring the situation. The fire personnel are trying their best. Praying for the safety of those trapped," Kejriwal said.

The cause of the fire was not immediately known.

Witnesses said columns of smoke were billowing from the spot and leaping up in the sky.

Last month fire inside an old building in the city killed 43 people and injured many others.

Chances of fire in Indian buildings are usually high as people ignore safety standards.