BEIJING - The source of cadmium contamination in the Liujiang River has been contained and drinking water in Liuzhou is safe and up to national hygiene standards, according to the Ministry of Health.

Cadmium contamination was discovered in the Longjiang River in Hechi on January 15 and soon spread downstream to the Liujiang River, the source of drinking water for 1.5 million residents of Liuzhou.

A plant belonging to Jinhe Mining Co. Ltd. is suspected of causing the pollution. Ten executives of the plant have been detained.

Zhang Lan, a researcher with the Chinese Center for Disease Control and Prevention, told the ministry's regular press conference on Wednesday that the source of the contamination has been contained, but that health officials will continue to monitor the rivers. City officials have also announced plans to build an alternative water source.

Health experts also warned that flu has been on the rise on the mainland and has no reached its peak.

Shu Yuelong, director of the National Influenza Center of China CDC, said this year had seen more cases of flu than last year, but the incidence is still within the normal range.