An under-construction bridge collapsed in Baishnabnagar area of Malda district on Sunday evening, killing two labourers and injuring seven others, police said.
The incident occurred when a girder of the second Farakka bridge gave away around 8:00 pm, they said, adding, more workers could be trapped under the debris.
Two labourers died, while seven others are under treatment at the Malda Medical College and Hospital, a police officer said. The condition of all the seven persons is stated to be critical, he said.
Personnel of the disaster management department, Malda, are conducting the rescue operation, the officer said.
The cause of the mishap is yet to be ascertained, police said.