A seven-storey hospital building in the city of Kolkata located in the eastern part of India was engulfed by fire claiming at least 73 people.

Most the dead people were patients of the hospital, a senior hospital official said.

The fire was brought under control late this morning by rescue workers and evacuation of bodies from the building started immediately, amongst those confirmd dead were two children seen taken out by eyewitnesses.

Patients who survived the fire were rolled out on stretchers and distraught relatives waiting outside the hospital as a thick layer of smoke covered the hospital building.

Of the 73 people dead only three were not patients of the hospital and 90 patients were safely evacuated.

Authorities believe the fire started in the basement, where flammable materials such as oxygen cylinders were stored.

Two dozen fire trucks were sent to douse the blaze and evacuate the building but it took the rescue workers time to bring the fire under control.