A Chinese professor who posted critical remarks about Mao Zedong on social media is the latest to find out that, under President Xi Jinping, taking issue with the Communist Party's past brings trouble.

Shandong Jianzhu University last week fired Deng Xiangchao, a professor in the school’s art institute, for his “erroneous remarks” on the Weibo social-media service. In the aftermath of the postings, he was vilified by protesters and online, with some calling him "the People's Public Enemy."

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