A prominent Chinese investment manager and three managers of a major stock brokerage have been formally arrested on insider trading charges following a collapse in share prices last year.

The charges announced Friday are the latest aftershock from the market rout. Authorities launched an investigation of securities traders in what was seen as attempt to deflect blame for massive investor losses.

The official Xinhua News Agency said fund manager Xu Xiang, who was detained in November, was charged with "stock market manipulation and insider trading," but gave no details.

It said the general manager of Citic Securities Ltd., Cheng Boming, and two other managers were arrested on similar charges.