(BBC) – China is sending investigators to Hunan province after local officials were accused of faking data at a water monitoring station, state media report.
The officials are alleged to have placed sensors intended to measure the water quality of Lujiang River inside bottles of mineral water instead.
The river, in Zhuzhou, is badly polluted by sewage water, reports say.
The environment ministry says it is investigating in Zhuzhou and “will seriously punish” any “violations”.
One monitoring sensor was even placed in a cup of tea instead of the Lujiang River, Xinhua news agency says.
The Chinese government has vowed to improve its efforts to monitor and combat pollution – but there continues to be concern about air and water quality in China.
In 2016, one government report said more than 80% of rural wells in the north-east contained water unsafe for drinking.