Probe hits shares of PetroChina and unit

Shares of PetroChina, the country's largest oil and gas producer, fell 4.4 per cent after the firm said three of its top managers were under investigation by Beijing for alleged violations of discipline.

The stock of Kunlun Energy, its gas distribution unit, tumbled 13.5 per cent.

Analysts said the lack of clarity about the allegations and whether they involved the firms' assets troubled investors, but they expected the share prices to recover, as replacements had been identified for the managers, who resigned for "personal reasons".

Li Hualin, PetroChina's board secretary and vice-president; Ran Xinquan, vice-president and general manager of operations at its largest gas field; and chief geologist Wang Daofu were being investigated, the State Council's State-owned Assets Supervision and Administration Commission (Sasac) said on Tuesday.

Li was also chairman of Kunlun, which benefited from asset injections from PetroChina at cheap valuations.

"[All the] positions have been filled with new candidates, and the change is unlikely to result in an adjustment in … strategy," a Standard Chartered research note said.