About 250 people fell sick in Anwara of Chittagong last night after inhaling ammonia gas that leaked from a pipe at the nearby DAP Fertiliser Company Limited.

Of them, 46 were admitted to Chittagong Medical College Hospital.

The incident occurred around 10:00pm when the factory was set to close.

Jashim Uddin, an assistant director of fire service, said at least 200 visitors to a nearby tourist spot fell sick as wind carried the gas to the area across the Karnaphuli river which flows by the fertiliser factory.

Firefighters were trying to contain spread of the gas till late last night.

Residents of the neighbourhood were advised through loudspeakers to stay indoors and breathe through wet cloths.

Meanwhile, many residents in Agrabad, Bandar, Halishahar, Patenga and Naval Academy complained that they could feel toxicity in the air even though they kept doors and windows at homes shut.

Firefighters working in the area said they felt burning sensation in their eyes and skin due to concentration of the gas in the area.

Amal Barua, managing director of the fertiliser factory, said the reason of the leakage could not be known. All the staffs were evacuated from the factory as soon as the leakage occurred, he added.