Public security authorities in Chinese cities on Friday warned against holding unauthorized demonstrations as access was cut to several Internet bulletin boards containing messages supporting anti-Japan protests.
Beijing is apparently trying to tighten controls in anticipation of more anti-Japan rallies rumored to be organized for the weekend.
Public security bureaus in Beijing, Shanghai and Wuhan in central Hubei Province issued identical statements on their Web sites, saying that any protests held without state permission are illegal.
People who hold rallies without permission or "endanger public safety or take actions that disrupt social order" during permitted rallies will be held legally responsible, according to the statements issued by the bureaus' spokesmen.