A total of 29 workers at a construction site in this capital city of northwest China's Ningxia Hui Autonomous Region were poisoned Saturday, but they have been out of danger after medical treatment, local sources said Sunday.

The workers felt dizzy, sick and vomitive on Saturday morning. They were

immediately taken to the Yinchuan Medical Center.

Local physicians cited absorbance of toxic chemical matters or food poisoning as the possible cause of the case. Local police and health departments were continuing investigation into the exact cause.

Source: Xinhua