"I pray that those who are injured recover at the earliest".
Governor Keshari Nath Tripathi visited the area.
"Bridge deserved better maintenance".
Banerjee said that thousands of people pass through the area and the government has to probe the accident.
News reports said more than 20 people were taken to local hospitals.
Principal Secretary of Transport BP Gopalika said additional state buses have been pressed into service to cater to residents in the affected areas.
She said there was a hut under the bridge and some labourers engaged in metro rail construction work used to stay. "Let lives count more than votes!" he added.
West Bengal Chief Minister Mamata Banerjee, now on a trip to Darjeeling in North Bengal, expressed concern over the incident and said her government will initiate a probe into the collapse. "The matter required to be enquired", he told reporters. She also ordered a high-level inquiry into the incident.
Eyewitnesses had said that the number of casualties could be very high given the busy location and the time of the collapse. "It was a 40-year-old bridge".
Rescue teams and the army have been deployed to help pull out those who could be under the rubble of the Majerhat bridge. Fire brigade, police and NDRF personnel rushed to the spot and carried out rescue operation.
"The collapse of a part of a bridge in Kolkata is deeply unfortunate".
It runs over the suburban railway network, which is the lifeline of the city. Suddenly I saw that a portion of the bridge collapsed. As the bridge collapsed during peak traffic hours, the Budge Budge-Sealdah railway line has been stopped.
The bridge, located in south-west Kolkata, is one of the major arterial roads that connects the neighbourhood of Behala to the rest of the city and has heavy movement of traffic round the clock.
Tuesday's accident took place at 4.30 p.m. when a segment of the bridge that measured about 250 ft collapsed, bringing down one minibus, five cars, and three motorbikes. It also extends to parts of the South 24 Paraganas district.
Police said on Tuesday night they were still trying to confirm if anyone else was trapped beneath the debris.