These people said they did not have direct evidence that Mr. Pan was sidelined by rivals.

Pan Yue, vice-minister at the environmental protection ministry, has taken personal responsibility for the deterioration of the environment, China Daily cited the Beijing Morning Post as reporting.

In a telling twist, the charges against Mr. Pan' s aides involved payments from companies seeking environmental approvals, said people who were told about the investigation.

Yue Pan , deputy director of China's State Environmental Protection Administration, sparked debate with his recent essay On Socialist Ecological Civilisation.

It has used this month's People's Congress to raise the status of Mr. Pan's agency to a ministry.