Kolkata, June 24 -- An under-construction private warehouse in West Bengal's Taratala area of west Kolkata collapsed on Wednesday afternoon, trapping at least 40 labourers under its debris, police said.

The structure, measuring a few hundred square metres, collapsed between 12:30 and 1 pm, police said.

Rescue operation is being carried out by the police, army and National Disaster Response Force (NDRF). Cranes and gas cutters are being used to remove the steel and concrete beams.

By 3 pm, 13 labourers had been rescued and admitted to the state-run SSKM Hospital, police said.

Urban development minister Agnimitra Paul and health minister Dr Sharadwat Mukherjee, among others rushed to the spot to oversee the rescue operation.

"The illeg...