Cash room and lockers on the other floor were however safe, police said, adding, seven fire tenders took two hours to extinguish fire.
A smoke was noticed at second floor and the fire department was called. By the time firemen reached, the fire had spread to 3rd floor, destroying all furniture, computer and server rooms, police said.
The cash room and lockers were safe as firemen managed to extinguish the fire before it could spread to the first and the ground floor.
Exact loss was being calculated by the bank staff.