A probe was launched into China Mobile corruption

Vice chairman and executive director Zhang Chunjiang of China Mobile, one of three major state-owned network operators in China and the largest in the world by mobile subscribers, has been prosecuted by Chinese authorities for suspected "serious personal violations".

China Mobile will watch the situation and make further announcements when appropriate about Chunjiang , as it said in a filing with the Hong Kong stock exchange.

Previously, China's official Xinhua news agency reported the investigation of Zhang, who also heads the Communist Party council at China Mobile's parent company. There are Communist Party councils at state-owned companies to keep them in line with official policy.

Corruption remains a widespread problem in China, where local media sometimes hesitate to expose graft for fear of government retribution. Thus, earlier this year two Chinese technology news sites briefly disappeared after carrying news reports that linked the son of Chinese president Hu Jintao to a corrupt deal for scanners in Namibia.