The second most senior official in China's populous Sichuan province is suspected of corruption, an official said Friday, the latest implicated in a high-profile anti-graft campaign.

Provincial governor Wei Hong is suspected of "severe disciplinary violations", generally a euphemism for corruption, anti-graft official Wu Yuliang said, and was "reflecting on his mistakes".

The allegation comes as part of a high-profile crackdown on corruption led by President Xi Jinping that has deposed several senior officials, notably former security chief Zhou Yongkang.

One of Zhou's power bases was Sichuan, in China's southwest with a population of some 80 million. A number of senior officials there have been investigated in recent years.

Official allegations of graft against high-level politicians are generally followed by an internal probe by China's Communist party, and sometimes lead to criminal proceedings almost guaranteed to end in conviction.

With corruption widespread in China, critics say there is a lack of transparency around Xi's campaign and it has been used for political infighting.

Wu, a vice chief of the ruling party's Central Commission for Discipline Inspection, said that such "twisted" views came from "a biased and wrong perspective", according to a press conference transcript.

But he revealed that only a small minority of officials found guilty of graft and other offences by the party end up prosecuted in criminal courts.

Just 14,000 party members faced legal proceedings as a result of discipline violations last year, he said, while 336,000 were punished internally.

He added that China was "in contact" with the United States over Ling Wancheng, the brother of Ling Jihua, a former chief of staff to Chinese president Hu Jintao.

Ling Wancheng reportedly fled to the United States when his brother became a target of the anti-corruption campaign.