BAGHDAD — Iraqi officials said more than 200 people were sickened by a chlorine gas explosion at a water purification plant in southern Iraq on Thursday night .
Dr. Saadoun al-Aalak, deputy director of Al-Sadr hospital in Amarah, said no one died in the Thursday evening blast at a water purification plant there. He said four people who were hospitalized overnight in critical condition from breathing the poisonous gas were released Friday morning.
The provincial governor, Sheyaa al-Sudani, says 200 sickened Iraqis initially sought medical treatment but most recovered quickly.
The cause of the blast in Amarah, about 200 miles (320 kilometers) southeast of Baghdad, was not immediately known, but there was no immediate indication of an attack.