BEIJING (AP) — Chinese anti-graft authorities announced an investigation into a former vice governor, making him latest senior provincial official to be ensnared in a crackdown that the country's new leadership hopes will show its determination to root out widespread graft.

The Ministry of Supervision said on its website that Guo Yongxiang was suspected of unspecified "serious disciplinary violations," a vague term that usually refers to corruption.

Guo's current title is chairman of Sichuan's provincial arts and literary federation, though that's believed to be a semi-retirement position for the 64-year-old official who was formerly vice governor of the southwestern province.

China's new leader Xi Jinping has made a crackdown on corruption and extravagant, wasteful work styles a key feature of his first half-year in power. He has vowed that the crackdown will target both low and senior-level officials.

Since he took over as head of the Communist Party in November, half-a-dozen vice-ministerial level officials have come under investigation, including the deputy party secretary of Sichuan province, Liu Chuncheng, who was fired following state media reports that he was suspected in influence-peddling and questionable real estate deals.

But observers noted that in the latest case, Guo's long association with China's now-retired former security chief Zhou Yongkang suggested the probe into Guo could be part of a larger factional struggle within the party's leadership.

Until the leadership handover in November, Zhou was the party's security boss and its No. 9 ranking official and wielded enormous influence over the police and paramilitary forces charged with maintaining internal stability at a time of growing unrest over corruption and uneven development.

"There's a reasonably high likelihood that this has to do with a vendetta against Zhou Yongkang," said Willy Lam, a professor at Chinese University of Hong Kong.

"We've had ample evidence in the past that officials who have been investigated are usually also a victim of factional strife, people who are on the losing end of a factional battle," Lam said.

Guo and Zhou's careers overlapped for 12 years and spanned the China National Petroleum Corp., the Ministry of Land and Resources and the Sichuan government.

In a 2002 report by Sichuan's official news portal, Zhou, who was then Sichuan's party boss, was shown visiting an elderly veteran communist cadre with Guo, who was the party committee's secretary general, bearing flowers and cake. Guo has also been cited in reports accompanying Zhou on visits to Sichuan petroleum executives and attending meetings in Beijing.