A major fire broke out in a chemical factory at Ganga Nagar near the city airport here on Wednesday evening.
Altogether 38 fire tenders were pressed into service to douse the blaze that was spotted at around 7.10 PM.
An explosion also took place during the fire fight at 11.30 PM and four fire fighters were injured in the blast. Many were suspected to have been trapped inside till late.
They were taken to hospital where their condition was stated to be stable, state fire department officials said.
The cause of the fire is not yet known.
Airport officials said air traffic was not affected due to the fire.
Local sources say that the ground floor of the factory functioned as the manufacturing unit of chemical fertilizers. The two upper floors were used for production of cloth materials. A lound thud was heard by the locals at around 7 in the evening. Huge quantity of inflammable substances were stored in the fertilizer section which ignited the fire.