The blaze sparked off at around 8:30 am in the factory located at Salkia in Howrah area near Kolkata.
Not only is the fire yet to be brought under control, the intensity of the fire is increasing, said officials.
As many as 12 fire tenders have been deployed at the spot and it has been estimated that it may be a couple of hours before the fire can be brought under control.
The fire fighting operations are also hindered by the fact that there are no water bodies in the near-by areas.
Thick smoke is seen emanating from the fire. The fire is reportedly spreading so fast that it has already caught up with another adjacent factory.