One day after professor Chen Hongguo posted his resignation letter [1] on Weibo that has triggered [2] hot discussion on academic freedom in China on December 23, 2013, his letter was deleted. A search on professor Chen's name on Sina Weibo shows the following message:
根据相关法律法规和政策，“谌洪果”搜索结果未予显示。
According to relevant regulations and policies, search results for “Chen Hongguo” are not displayed.