On May 14, 2013, Hong Kong's South China Morning Post published an article entitled "Eight Activist Lawyers Detained in Sichuan Over 'Illegal Jail' Have Been Released." An excerpt:
Eight prominent lawyers, who have been arbitrarily detained in Sichuan province on Monday, have been released from police custody. Seven of them tried to visit a detention centre; the eighth was part of a rescue group that arrived later.
The seven detained lawyers had attempted to visit an "illegal" detention centre in Ziyang. Later that day a separate group of four lawyers arrived to try to rescue them, but they were also detained.
Three in the later group had been released early, but police in Ziyang kept the fourth, Li Heping (李和平), in detention. By Tuesday morning, all had been released.These screenshots show that on May 14 Baidu began censoring searches for "Lawyers Detained and Beaten While Calling Attention to Black Jail in Ziyang" (律师围观资阳黑监狱被殴打监禁).
. . . .
The seven lawyers from Beijing, Chongqing and Wuhan, including renowned activists Tang Jitian (唐吉田) and Jiang Tianyong (江天勇), had gathered in Ziyang on Monday morning to raise awareness over what they say is an illegal detention facility in the prefecture-level city.
These screenshots show that the specific phrase targeted by search engines like Baidu and Qihoo for censorship is "Ziyang Black Jail," and they are restricting search results to a white list of about a dozen web sites controlled by the central government and the Communist Party.
These screenshots show that Sina's Weibo and Tencent's Soso were returning no search results for "Ziyang Black Jail," just censorship notices.