Twelve people were killed and over 40 feared trapped after a decades-old, four-storey building collapsed in south Mumbai's crowded Dongri neighbourhood around 11:40 am on Tuesday. Eight people have been rescued.
Three large teams of the National Disaster Response Force (NDRF) are at the site, looking for survivors. The area, full of dilapidated buildings on narrow lanes, was also flooded in heavy rain in the past weeks.
Ten ambulances and fire trucks are parked some distance away from the building as the lanes are too narrow for them to enter.
"We heard a loud noise. Everybody shouted, 'building is falling, building is falling'. I ran. It felt like a big earthquake," a teenager who saw the building fall told NDTV.
"I saw bodies... There were some seven-eight families in the building," another eyewitness told NDTV.
In visuals of the rescue operation, NDRF personnel in their bright orange safety gear are seen trying to remove concrete blocks as they probe the openings amid the debris for signs of life.
The authorities said this was a "level 2" incident - while level 1 is the most serious under the system that measures the severity of a building collapse.
Crowds thronged about the narrow lanes - where it would be extremely difficult for heavy machines to reach - and formed a human chain to pass down with their bare hands small debris like wooden blocks and bricks towards the outer area of the neighbourhood.
"The building was 100 years old. We have given permission to redevelop that area... We will know after investigation if the redevelopment initiative was delayed. Right now we are focusing on rescuing trapped people," Maharashtra Chief Minister Devendra Fadnavis told reporters.
A man who used to live at Dongri alleged the Brihanmumbai Municipal Corporation is slow on allowing people to repair their old homes in the area. "I applied for permission several times, but the BMC delayed it. All of this (building collapse) wouldn't have happened if they had allowed us to repair our own building. We don't want to wait for them. We will use our own funds," said the man, looking at the rubble that was once a building he recognised well.
Building safety is a major issue in Mumbai, one of the world's most crowded cities next to Dhaka in Bangladesh, according to the World Economic Forum.
In May, the civic agency BMC in the country's financial and entertainment hub had identified 499 buildings as "dangerous"; it was 619 last year.
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