Nobody was injured in the incident, they said.
The fire broke out at around 8.45 PM due to some electrical malfunction in an office room, located on the 10th floor of the LIC building in the C R Avenue in Bowbazar police station limits, a senior Kolkata Police officer said.
Five firetenders took almost 40 minutes to douse the blaze, he said.
"The cooling process is still underway. None got hurt or trapped. We are yet to ascertain the extent of damages. The situation is under control, the officer added.