KOLKATA: A fire swept through a six-storey building housing an illegal market in the eastern Indian city of Kolkata on Wednesday, killing 13 people who were unable to escape the inferno, local officials said.

“The death toll in the Surya Sen Market fire has jumped to 13,” state fire services minister Javed Khan told AFP.

“The market has only one exit point and those who stayed in the market at night were trapped after the fire broke out.”

Hundreds of firefighters were at the scene of the blaze near the railway station in the centre of the former colonial capital of India, where decrepit and poorly maintained buildings are vulnerable to fires.

The victims of Wednesday's blaze were thought to be men who were sleeping in the building when the fire broke out at around 04:00 am (2230 GMT) director of fire services for West Bengal state Gopal Bhattacharya told AFP.

“The market housed in the two floors of the building has no legal sanction,” he explained.

In late 2011, 90 people were killed when a fire engulfed a hospital in Kolkata while in March 2010 a huge blaze on one of the city's most exclusive streets left at least 43 dead.