Messages posted on websites in China called for anti-Japan demonstrations this weekend to protest "Japanese aggression" in connection with the arrests of Chinese activists who sailed to the Senkaku Islands last week.
Chinese authorities routinely delete messages on social networking sites that call for public demonstrations they want to prevent. The posts calling for Sunday's anti-Japan protests, however, remained on China's major Weibo microblogging site.
Messages listed the locations of about 10 cities. They included the northern metropolis of Tianjin, Chengdu in Sichuan Province, Hangzhou and Wenzhou in Zhejiang Province, and Guangzhou and Shenzhen in Guangdong Province. Beijing and Shanghai were not on the list.
Protests erupted in several major cities after Japanese authorities arrested and on Friday deported Friday the 14 Chinese who sailed to the islets in the East China Sea two days earlier. The uninhabited Senkakus are under the jurisdiction of Ishigaki in Okinawa Prefecture.
Protesters held sporadic anti-Japan demonstrations in Beijing, Shanghai and other cities Friday.
The messages posted on Weibo called for large demonstrations Saturday and Sunday to protest "Japanese aggression in Diaoyu, (which is) Chinese territory." The messages said the protests would start at 10 a.m., and listed meeting places and marching routes.
The posts also criticized the Chinese government for not taking action to protect the activists.
"The People's Liberation Army must protect Diaoyu," one message read. Another said that China should "seize back the islands by going to war."
Widespread anti-Japan protests took place in China in September 2010 following the arrest of the skipper of a Chinese fishing trawler that rammed two Japan Coast Guard vessels trying to shoo it away from the Senkakus.