Indian police on Friday registered a case of murder and attempt to murder against the company that had been building a flyover which collapsed in Kolkata, killing at least 23 people and injuring dozens.

Three officials of IVRCL Infrastructure were arrested and seven other employees detained in connection with the collapse of the unfinished overpass in the busy Burrabazar area of the city, officials said on Saturday.

The employees are being questioned over possible charges of murder and culpable homicide, crimes that are punishable by death or life imprisonment, and criminal breach of trust, which carries a prison sentence of up to seven years, police said.

Police also sealed the company's Kolkata office.

Two senior engineers from Kolkata Metropolitan Development Authority, which was a joint venture partner in the project, have also been suspended by the state government, local channel NDTV reported.

Chief Minister Mamata Banerjee, whose centre-left party is seeking re-election soon in the state of West Bengal, where Kolkata is located, said those responsible would not be spared.


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More than 100 people were rescued, many with serious injuries, but chances of finding more survivors dwindled after authorities removed crushed cars and a bus from the rubble in the commercial district near the city's Girish Park.

"It is being ensured that there are no more dead bodies under the debris," SS Guleria, deputy inspector general of the National Disaster Response Force, told Reuters news agency.

Local TV footage showed a street scene with two auto rickshaws and a crowd of people suddenly obliterated by a mass of falling concrete that narrowly missed cars crawling in the traffic jam.

IVRCL Infrastructure was contracted in 2009 to build the flyover but the company had missed several deadlines for completion.

The flyover had spanned nearly the width of the street and was designed to ease traffic through the densely crowded Burrabazar neighborhood.

"We completed nearly 70 percent of the construction work without any mishap," IVRCL official KP Rao said on Thursday. He was not among those detained on Friday.


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"We have to go into the details to find out whether the collapse was due to any technical or quality issue."

Years of delays may have led to corrosion to metal elements of the flyover, according to rescuers. Crowds of residents tried to help trapped people. 

"The government wanted to complete the flyover before the elections and the labourers were working to a tight deadline. Maybe the hasty construction led to the collapse," said Ravindra Kumar Gupta, a grocer who pulled out six bodies, together with his friends.

"Every night, hundreds of labourers would build the flyover and they would cook and sleep near the site by day."

Source: Al Jazeera and agencies