This is the deadly moment a flyover collapses onto a street below killing at least 14 and injuries dozens more.

Locals used their bare hands as soon as the dust settled to try and get to those who are trapped, and now huge cranes and other equipment has been drafted in to help with the rescue misssion.

More than 70 people have been pulled alive from the rubble and taken to hospital following the collapse in Kolkata in western India.

One witness told New Dehli Television News: "The area was very, very crowded. Motorised rickshaws, taxis, there was a lot of traffic."

While another added: "We heard a loud rumble and then saw a lot of dust in the sky."

Army troops and personnel from the National Disaster Response Force joined efforts to extract people from vehicles that lay under under the 100-metre length of metal and cement that snapped off at one end.

Television images showed the bloody legs of some of the trapped people jutting out of the collapsed girders and concrete slabs.

Resident Ramesh Kejriwal told Reuters: "The concrete had been la!d last night at this part of the bridge."

Mamata Banerjee, the top elected leader in the state, visited the collapse site and said a private builder had missed several deadlines for completing the overpass.

The contract for the overpass was signed in 2008 and it was expected to be completed within two years.

She accused the previous communist government in West Bengal of not adhering to building regulations.

Building collapses are common in India, where builders use poor enforcement of regulations and use substandard materials.

Mrs Banerjee said: "We will take every action to save lives of those trapped beneath the collapsed flyover. Rescue is our top priority."

A newspaper reported last November that Banerjee wanted the flyover - already five years overdue - to be completed by February.

Project engineers expressed concerns over whether this would be possible, The Telegraph said at the time.

Watch the video below: