Three senior police officers in Qingdao, Shandong province, are being investigated on bribery charges that are believed to be linked to a major gang case in 2010.

Prosecutors have detained Zhao Min, head of the anti-terrorism division at the city's Public Security Bureau, and two deputy crime squad heads.

A total of 53 officials were implicated following a crackdown on an organized crime group headed by Nie Lei in September 2010. Many of them were in the city's political and legal departments.