UPDATES:

Rescue operations continued through out the night.

Rescue operations continue after the collapse of an under-construction bridge in #Kolkata pic.twitter.com/9UXMWVcQCt ANI (@ANI_news) April 1, 2016 Death toll rises to 21, 85 injured according to Mamata Banerjee.

3 more NDRF teams sent to #Kolkata bridge collapse spot keeping in view the prolonged rescue ops. 10 teams with 400 rescuers on spot now.



We will take care of all the expenses of all the injured, we hope for their speedy recovery: WB CM on #Kolkata bridge collapse ANI (@ANI_news) March 31, 2016

Army has deployed 4 columns of rescue personnel. There are 3 medical teams, 2 ambulances, surgeons and nursing assistants in each team. One Engineer team of Army has also reached with special equipment's.

Helpline numbers: 1070, 033-2214-3526, 033-2253-5185, 033-2214-5664 Call us at 8585902617 in case of any blood donations in #Kolkata requirements. Kolkata- Reprise (@TweetKolkata) March 31, 2016

Shocked & saddened by collapse of under construction flyover in Kolkata. Took stock of the situation & rescue operations. Narendra Modi (@narendramodi) March 31, 2016

Horrifying moment that flyover came crashing down in #Kolkata today. Truly terrible. pic.twitter.com/yk1ZbnQnkp Shiv Aroor (@ShivAroor) March 31, 2016

Two NDRF units have been rushed to the spot to help in rescue operations. (Photo: Shyam Sundar Ghosh Two NDRF units have been rushed to the spot to help in rescue operations. (Photo: Shyam Sundar Ghosh

Police, fire brigade and disaster management personnel have rushed to the accident site and started rescue work. Cranes have been pressed to remove the debris.

The injured people have been shifted to the Calcutta Medical hospital for medical aid.



WATCH: Desperate attempts being made to lift up fallen under-construction bridge to rescue trapped people in Kolkatahttps://t.co/qyt7XktjuX March 31, 2016

Two NDRF units of 70 members have also been rushed to the area to help in rescue operations. However, there was little sign of a coordinated rescue operation, with access for heavy lifting equipment restricted by the proximity of buildings on either side of the flyover and heavy traffic.

"Spoke to DG NDRF who apprised me of situation at the accident site in Kolkata. NDRF teams rushed to spot for rescue ops," Home Minister Rajnath Singh said

IVRCL, the company that was building the #Kolkata flyover, says it was "an act of God". Is it suggesting that the FIR should be against God? T S Sudhir (@Iamtssudhir) March 31, 2016

Taxi buried under the debris of the collapsed bridge. (Photo: Shyam Sundar Ghosh Taxi buried under the debris of the collapsed bridge. (Photo: Shyam Sundar Ghosh

The flyover has been under construction since 2009 and has missed several deadlines for completion. Television footage from the scene showed a bloody hand reaching out from under what appeared to be a massive girder. People were trying to hand bottles of water to survivors pinned underneath.

Chief Minister Mamata Banerjee has cancelled her election rally in West Midnapore and is at the site of the accident.

In the election-bound state, senior BJP leader Kailash Vijayvargiya lost no time in blaming her government for the tragedy. "Mamata ji's government is responsible for this, we want action to be initiated against the ministers and people associated" Vijayvargiya said.

Under-construction bridge collapsed near the famous Ganesh Talkies in north Kolkata's Girish Park area today, killing several people and creating panic in the area. In Pics



A portion of the Vivekananda Flyover crashed and fell on the busy main road traffic in the congested Barabazar area. Many passenger vehicles, trucks and rickshaws were seen under the debris but it was not immediately known as to how many people were trapped.

A loud rumble was heard by the residents of the area which was followed by a huge cloud of smoke.

"It was a powerful collapse, sent shivers down my spine. People here are very scared," said and eyewitness.

Army has been called in to assist in the rescue work. (Photo: Shyam Sundar Ghosh Army has been called in to assist in the rescue work. (Photo: Shyam Sundar Ghosh

Some workers have been pulled out from under the concrete. Civilians are also helping out in rescue operation.

"Cement and concrete were poured in yesterday only, it suddenly collapsed today," said another eyewitness.



The area is considered as one of the most congested areas of North Kolkata.

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