The cause of the fire is yet to be ascertained.

2:21 pm: WB Disaster Management Minister Javed Khan said, "it is heard that the fire broke out from an air condition machine". The firefighters are trying to bring the fire under control.

Update 12:20 pm: West Bengal Chief Minister Mamata Banerjee and Disaster Management Minister Javed Khand are on their way to New Secretariat Building. Police Commissioner Surajit Kar Purkayastha and Minister Subrata Mukherjee have already reached the spot.

A fire broke out in Kolkata's government office – New Secretariat Building – on Friday morning.

The fire started at around 10:30 am on the top floor of the 10 storey building of the New Secretariat. At least 20 fire engines have been rushed to the spot to control the fire, according to TV news reports. Disaster management teams have also been rushed.

Several important documents of the state government were damaged after a major fire broke out on Friday at the multi-storeyed New Secretariat building located on Strand Road in the central business district here. As many as 26 fire engines and disaster management teams were called into action to control the blaze, state Fire Services Minister Javed Khan, who visited the spot, said.

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The high rise houses a number of government offices including important departments like panchayat and PHE department, transport department, PWD and others. The building houses the state government’s anti-corruption bureau office too.

The fire department officials claimed that few people were inside when the fire broke out, and they have all been rescued.

State fire minister Javed Khan along with senior cabinet ministers have rushed to the spot.

So far, no injury or casualty has been reported. The cause of fire is yet to be ascertained , though  police have ruled out possibility of  sabotage behind the incident.