At least four workers have died from a Thursday morning fire at a six-storey textile factory in Tehran.

The Fire Marshall reported that the number of casualties may increase.

Jala Maleki said the fire started on the third floor of the building and it was spreading to the other floors.

He said firefighters rescued several workers from the roof, adding that one worker jumped from the building in panic.

Maleki said the casualties include one man and one woman, and he is concerned that the number of people killed by the fire may rise, as some survivors remain in critical condition.

The cause of the fire has not been determined.