China has detained a prominent scholar who helped blind dissident Chen Guangcheng flee to the United States two years ago and has banned books by eight writers in an escalating crackdown on dissent. Guo Yushan, a founder of the Transition Institute, a think-tank that researches business regulations, reform and civil society, was detained on Thursday, his wife, Pan Haixia, said. More than 10 police officers took him away along with his laptop, wireless router, mobile phone and iPad, she said. Guo was instrumental in helping Chen escape house arrest in his village in 2012. Chen travelled to Beijing where he sought refuge at the U.S. embassy, sparking a diplomatic row between China and the United States. Authorities shut down Guo's institute last year. In a telephone interview, Pan said Guo's detention could be related to the detention of Shi Lin. Activists describe Shi as an art editor at Peking University and say she was detained after she tried to put up posters on campus expressing support for pro-democracy demonstrations in Hong Kong. In a picture on her Twitter account, she can be seen wearing a face mask with a yellow ribbon on it. The ribbon is a symbol of the protests. Guo was detained on a charge of "causing a disturbance", according to Pan and his lawyer, Li Jin. Police did not give Pan a reason for Guo's detention. Li said she had applied to meet him but had not heard whether she could. "We just want to know the truth," Pan said. "We hope the police will investigate this thoroughly and release him quickly." Police could not be reached for comment. If charged and convicted, Guo could face up to five years in prison. http://english.ahram.org.eg/News/112983.aspx