PetroChina Co, a listed arm of China's largest oil and gas producer by output, was sued by an Belgian investor for violating US securities laws by failing to disclose corruption exposed by the Chinese government investigations, Bloomberg reported Wednesday.

Calls to Beijing-based China National Petroleum Corp (CNPC), parent company of PetroChina which is listed on three major global stock exchanges of New York, Hong Kong and Shanghai, went unanswered by press time Wednesday.

Belgian investor Johan Broux filed the complaint Tuesday in Manhattan federal court seeking to represent all buyers of PetroChina securities from April 26 2012 to August 27 of this year, claiming that PetroChina shares dropped more than 3.5 percent on August 28 on news that two Chinese government agencies were investigating company officials for corruption, Bloomberg said.

The Bloomberg report also said that the complaint named as defendants chairman and president Zhou Jiping, chief financial officer Yu Yibo and two former senior executives - ex-CFO Zhou Mingchun and former board chairman Jiang Jiemin.

In the complaint, Broux sought unspecified damages, the report said.

Hao Junbo, a lawyer specializing in claim settlement in stock and securities sector, was quoted by news portal NetEase as saying that PetroChina has damaged the interests of its shareholders due to a lack of efficient management.

Hao noted that it is "more difficult and complicated" for the shareholders in the Shanghai Stock Exchange to sue Petro­China than for the investors in the US stock exchanges, as "the shareholders of Petro­China in the A-share market have to wait until the China Securities Regulatory Commission has announced administrative penalties on the company."

Jiang Jiemin, head of the State-owned Assets Supervision and Administration Commission (SASAC) of the State Council and deputy secretary of the SASAC committee of the Communist Party of China (CPC), has been removed from office on the suspicion of serious disciplinary violations, Xinhua News Agency reported Tuesday.

Jiang, the former board chairman of CNPC, was nominated as SASAC chairman in March this year.

Previously, Wang Yong­chun, deputy general manager of CNPC, was also sacked for serious disciplinary violations, according to Xinhua.