More than 150 people were posioned during a chlorine gas explosion late Thursday in Iraq's southern city of Amarah, local official said on Friday.

About 150 people were sent to local hospital for treatment after the blast at a water purification plant in Amarah, which locates 320 km south of Baghdad, some of them cannot breath due to the chlorine gas, but most of them are OK now, a local city council member told Xinhua on condition of anonymity.

"Nobody died in the incident, and the city council has started to investigate the reason of the blast," he added.

This was not the first time that such kind of accident occurred in Iraq recently. Last week in the eastern province of Diyala, 70 people were also wounded in a chlorine gas explosion. It was not immediately clear whether those were attacks by insurgents or not.