Almost 500 people suffered respiratory and other symptoms after a chlorine gas leak in southern Iran.
A report said 475 victims were taken to hospitals in the city of Dezful, some 500 miles south-west of the capital, Tehran.
Forty-five people were kept in hospital and the rest were released.
The gas leaked from reservoirs in an abandoned warehouse belonging to the local water supply company.
Dezful, with a population 250,000, lies in the oil-rich Khuzestan province.