An under-construction building at the Kannauj railway station collapsed on Saturday afternoon, trapping around two dozen workers under the rubble, a senior official said.
Six workers have been rescued and rushed to hospital.
Initial visuals from the site showed scenes of chaos and confusion with crowds, clouds of dust and broken beams as people tried to rescue those who had been trapped.
"According to preliminary information, the incident occurred when the under-construction shuttering of the roof collapsed," said District Magistrate (DM) Shubhrant Kumar Shukl said.
"Our first priority is to rescue the workers who are trapped. We are using all resources at our disposal for the rescue efforts," Shukl, who had rushed to the spot along with other senior officials to oversee the rescue operation, added.
A shaken Mahesh Kumar, among those at the site, recalled his narrow escape.
"As soon as the concrete was poured over the shuttering, it suddenly collapsed. Everyone on it fell. I was standing at the edge and managed to escape," he said, Taking cognisance of the incident, Uttar Pradesh Chief Minister Yogi Adityanath directed officials to ensure safe recovery of those trapped inside and their proper medical treatment.
State Relief Commissioner Bhanu Chandra Goswami is in touch with the Kannauj district administration for all possible help in relief work, state government officials said.
Teams of NDRF and SDRF have been deployed at the site where frantic efforts are underway to rescue the workers. Ambulances have been kept on standby to provide first aid and take the injured to hospital.
The emergency ward at the district hospital is on alert and doctors put on standby, officials said.
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