Two labourers were killed on Thursday morning after falling off a scaffold erected for the renovation of Metropolitan Building, on JL Nehru Road. One of the men died on the spot, while the other succumbed to his injuries a few hours later at SSKM Hospital.

Police have started a case of negligence against a private agency that was given the sub-contract for the renovation work.

Sanjay Mukherjee, deputy commissioner of police (headquarters), said the incident occurred around 11.30 am when Jugal Naskar, 32, and Mohammad Ishraful, 22, were cleaning the exterior wall of the building. ?They were working at the third-floor level. The two fell off when a portion of the frame collapsed,? he said.

Naskar, a resident of Mograhat, in South 24-Parganas, fell straight on to the pavement. ?His head was smashed. The doctor at the hospital declared him dead,? said an officer of New Market police station.

After falling off the frame, Ishraful hit two iron bars at the second-floor level. ?His limp body dangled between the two bars. Before other labourers could reach him, Ishraful slipped through the gap and fell on the pavement,? said Mukherjee.

?He was brought here in a critical condition, unconscious and gasping for breath. We immediately put him on oxygen. Two hours of effort to save him proved futile. He died around 2 pm,? said a doctor of SSKM Hospital.

?During preliminary investigation, we came to know that the contract for renovation of the building was awarded to Mackintosh Burn, which gave the sub-contract to Caltech. A case of negligence causing death has been started. We will bring in forensic experts to ascertain how and why the frame collapsed,? said Mukherjee. Neither of the companies was available for comment.

?The bodies have been sent for post-mortem and will be handed over to the families on Friday,? said an officer of New Market police station.