According to reports, the fire broke out at around 10:20 pm at Jamunalal Bazar Street.
Fire brigade sources said that there was no report of any casualty so far.
Fifteen fire tenders were engaged to battle the blaze and the building was evacuated, said fire services minister Javed Khan who visited the site to supervise fire fighting operations.
Sources said that the fire fighting operations proved difficult as the building was located in a congested lane. The cause of fire and the extent of damage are yet to be ascertained.