A former deputy Communist party chief in China's restive Xinjiang region is being investigated for "disciplinary and law violations", authorities said Friday, the latest high-ranking official to fall in the country's anti-graft campaign.

Yang Gang, 60, who was the Communist number two in Xinjiang from 2006 to 2010, is being probed for "suspected severe violation of discipline and the law", the party's Central Commission for Discipline Inspection announced.

The phrase is commonly used as a euphemism for corruption.

He is currently vice director of the economic committee of China's Political Consultative Conference, a debating chamber that is part of the Communist-controlled governmental structure.

The investigation makes Yang at least the 17th official at vice-ministerial level or above to fall since a once-in-a-decade power transition in November last year that anointed Xi Jinping as the party's secretary general.

Xi, who became head of the state in March, has taken a hard line against graft, waste and extravagance since coming to power a little over a year ago.

He has warned that corruption could destroy the party and threatened to crack down on high-ranking officials, described as "tigers", along with low-level "flies".

High-profile cases that have emerged over the past year include the sacking of Jiang Jiemin, head of China's state-owned assets watchdog, and Li Dongsheng, formerly a vice minister of public security.

But critics say no systemic reforms have been introduced to increase transparency to help fight endemic graft.