NEW DELHI • The Indian authorities were investigating the cause of a devastating fire that killed at least 43 people in a factory in central New Delhi yesterday, as relatives of the workers trapped inside waited at a hospital mortuary to identify the dead.

Firefighters had to fight the blaze from 100m away because it broke out in one of the area's many alleyways, too narrow for vehicles to access, the authorities said.

A resident of the area, Mr Mohammed Naushad, said he was woken by people wailing around 4.30am. He went outside to find smoke and flames shooting out of a building near Sadar Bazaar, New Delhi's largest wholesale market for household goods.

Inside, he found the fourth floor engulfed in flames. One floor below, he saw "20 to 25 people lying on the floor".

"I don't know if they were dead or unconscious, but they were not moving," Mr Naushad said. He said he carried at least 10 people out of the flames on his shoulders and into the arms of emergency responders.

Outside the mortuary, which was guarded by dozens of police officers, some of the workers' relatives said they received phone calls from the men trapped inside, who begged them to call the fire brigade.

Many of the men were migrant workers from the impoverished border state of Bihar in eastern India, relatives said. They earned as little as 150 rupees (S$2.90) a day making handbags, caps and other garments, sleeping in the factory between lengthy shifts.

Many of the victims were asleep when the blaze began, according to Mr Yogesh, a police spokesman who goes by one name.

The cause of the fire was not immediately clear. A case of culpable homicide not amounting to murder was registered against the building's owner, but no arrests were immediately made, said New Delhi assistant police commissioner Anil Kumar Mittal, adding that the authorities were investigating whether the factory was operating legally.

Fires are common in India, where building laws and safety norms are often flouted by builders and residents.

In 1997, a fire in a movie theatre in New Delhi killed 59 people. In February this year, 17 people were killed by a fire in a hotel in the capital that started in an illegal rooftop kitchen.

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