A 30-metre span of the highway bridge fell on a busy roadway at approximately 4:30 p.m. local time on Tuesday, trapping several vehicles underneath. A bus and five other vehicles fell with the section of concrete, the Associated Press reported.
There was no official count of injuries or deaths, although rescue crews were seen pulling several individuals from the rubble.
The approximately 40-year-old bridge is a main route into southern Kolkata, with thousands of cars crossing over it every day. The span runs over a railway line, the Majerhat Railway Station and a busy roadway.
The cause of the collapse has not been determined.
“Police are investigating the matter,” Mamata Banerjee, chief minister of the state of West Bengal, told reporters on Tuesday in Darjeeling.
“A detailed investigation will be done but right now our focus is rescue and relief efforts.”
West Bengal’s governor, Keshari Nath Tripathi, said the state’s Public Works Department (PWD) and the railway administration were responsible for maintaining the bridge. “There was a report on a pit here for quite some time,” he told reporters on Tuesday, adding that he wasn’t sure if the PWD noted it.
Tripathi said the bridge “deserved better maintenance.”
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Kolkata’s traffic police reportedly told local officials on several occasions this year that the bridge needed work.
A police official warned in July that the bridge was in bad shape ahead of monsoon season, according to a report.
“Monsoon has turned the busy Majerhat bridge, which is used by thousands of vehicles … into a death trap,” the unnamed top official told the Times of India, in a story published July 1.
“Commuters’ lives are at risk as small pools have formed on the bridge,” the official said.
Records show the PWD put out a tender for surface repairs on the bridge in April.
Workers began fixing potholes on the bridge in July, but PWD officials reportedly said it was not possible to do a full repair because of monsoon season.
“This is one stretch of [Diamond Harbour] Road that witnesses maximum traffic, and therefore we cannot shut it down. We have to wait for the festival to end before starting a complete overhaul.”
The bridge collapse is the second deadly incident in Kolkata’s recent history. The steel Vivekananda bridge collapsed on March 31, 2016, killing 26 people and injuring dozens more. The bridge was under construction and not in use at the time.
WATCH BELOW: CCTV captures 2016 bridge collapse in India
Dozens of people were killed when a major highway bridge collapsed in Genoa, Italy, last month. An engineer had flagged the bridge as a “failure” years before the incident occurred.
West Bengal officials say they will conduct a full investigation into the Majerhat bridge collapse.
— With files from the Associated Press