More than 200 protesters have been holding an angry vigil at Peking University since Wednesday to protest a professor's controversial remarks on mentally-ill petitioners. Police have taken away more than 50, a university official said yesterday.

Sun Dongdong, head of the university's judicial expertise center, set off a firestorm by suggesting in the March 23 issue of China Newsweek that 99 percent of people who repeatedly petition the government were mentally ill.

Although he said later he had been quoted out of context and apologized, protesters have rallied in front of the university with banners calling for Sun to be fired.