The Kolkata police on Friday detained 10 executives of the company constructing the Vivekananda Road flyover in Kolkata, which collapsed on Thursday. The officers went to Hyderabad earlier to arrest officials of IVRCL group, a blacklisted company that had won the contract for the flyover. Police have reportedly registered three FIRs in the case, including charges of murder, reported CNN-IBN.

At least 90 people were rescued in overnight operations by Friday morning at the site in Kolkata’s Burrabazaar area. While there are conflicting reports on the number of deaths, Kolkata Police Commissioner Rajeev Kumar said 24 bodies were recovered and at least 110 people were injured. A state forensic team also collected evidence from the area on Friday. Though the incident has begun to be politicised ahead of approaching state elections, Home Minister Rajnath Singh called Chief Minister Mamata Banerjee and offered the Centre's help in the matter.

Representatives of the firm, which had earlier appeared to evade responsibility for the tragedy on Thursday by calling it an “act of God”, said the incident was “merely an accident” and that they would cooperate with the police investigation. “We are also anxious to know why it happened,” one of the representatives, Sita, said, adding that the company alone cannot be blamed for the nine missed deadlines as the government had not provided clearances on time, The News Minute reported. The company also suggested a bomb blast could have caused the collapse.

SS Guleria, the director general of the National Disaster Response Force officials said the relief work would end by mid-day on Friday and the chances of finding more survivors are low. Many of the people rescued are in critical condition, officials said, mainly as a result of multiple fractures.

Disaster response personnel used cranes, concrete and metal cutters, as well as heat detectors to find people under the wreckage. It is unclear how many others are still trapped in the rubble. The massive crowds that gathered around the collapse site also hindered rescue operations, Guleria said.

A 150-metre section of the 2.2-km flyover collapsed on Thursday, trapping hundreds of people and crushing dozens of vehicles. Construction work on the much-delayed project had been stepped up over the past few months, leading many to suspect that hasty and shoddy work was the root cause of the collapse.

Political reactions have included the Trinamool Congress promising to take action for the incident, and the Bharatiya Janata Party asking for a Central Bureau of Investigation inquiry into the flyover collapse. Chief Minister Mamata Banerjee has blamed the former Left government in the state for awarding IVRCL the contract in 2007. ANI reported that members of the BJP and Congress held candlelight vigils for the victims on Friday evening.