The governor of the eastern Chinese province of Fujian and former chief of state-owned energy giant Sinopec is being investigated for suspected corruption, state media said Wednesday.

Su Shulin, who is also the deputy chief of the ruling Communist Party's provincial committee in Fujian, was suspected of "serious disciplinary offences" -- normally a euphemism for corruption -- the official Xinhua news agency reported.

It cited the Central Commission for Discipline Inspection (CCDI), the party's anti-graft watchdog.

Su is a former chief of Chinese oil giant Sinopec, which ranked second on Fortune magazine's Global 500 company list this year, and the news comes less than a month after another top executive of the company was ousted from the Communist Party for corruption.

Ex-Sinopec president Wang Tianpu, who was put under investigation in April, was found to have taken bribes, offered benefits in exchange for his own promotion, and embezzled public assets, the CCDI said.

The investigation into Su comes as part of a high-profile crackdown on graft by current President Xi Jinping that has deposed several senior officials, notably former security chief Zhou Yongkang who, like Wang and Su, had a background in the oil industry.

Xi has pursued the anti-graft drive since taking office, vowing to go after both senior "tigers" and low-level "flies".

But critics say the drive is open to factionalism and that the Communist Party has failed to introduce systemic reforms to prevent graft, such as public disclosure of assets.