Another senior official of oil giant China National Petroleum Corp has been detained by the authorities, which shows that the anti-corruption campaign in the energy sector has not ended following the announcement of an investigation into retired Party leader Zhou Yongkang.

Wang Lixin, head of the discipline and inspection department at the State-owned company, has been held for investigation since late September, according to Bloomberg News, which quoted two officials who requested anonymity because the information is not public.

As the country's biggest oil and natural gas producer, CNPC has been a major target of the anti-graft campaign since August 2013.