- Several trapped under the debris, including passengers in a minibus
- The flyover collapsed in the busy Burrabazar area during lunch hour
- Army called in, earlier residents tried to rescue people with bare hands
The overpass that had been under construction since 2009 crashed onto vehicles and people below during lunch hour in a busy commercial area of Kolkata.
The army has rushed in more than 150 soldiers to help locate and rescue those trapped under the debris. Witnesses initially spoke of a poorly coordinated effort to bring in heavy-lifting equipment with buildinfs on either side of the flyover and heavy traffic adding to the challenges.
"The problem is that nobody is able to drive an ambulance to the spot," said Akhilesh Chaturvedi, a senior police officer.
Chief Minister Mamata Banerjee, seeking re-election next month, rushed to the scene to survey the damage. She faces tough questions over who was responsible.
The Telegraph reported last November that Ms Banerjee wanted the project - already years late - to be completed by February. Project engineers expressed concerns over whether this would be possible, The Telegraph said at the time.
People were trying to hand bottles of water to survivors pinned underneath.
Helpline numbers: 1070, 033-2214-3526, 033-2253-5185, 033-2214-5664
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