TIMELINE: China's academic arrests

December 2000 -- Qin Guangguang, a former editor, scholar, and currently a businessman with permanent residency in the United States, is taken into custody by Chinese authorities on suspicion of spying for Taiwan.

February 11, 2001 -- Gao Zhan, a sociologist associated with American University in Washington, is arrested at Beijing airport along with her husband, Xue Donghua, and her 5-year-old son, Andrew.

February 25, 2001 -- A 45-year-old business professor with U.S. citizenship at the Hong Kong City University, Li Shaomin, is arrested in Shenzhen, China.

March 9, 2001 -- Gao Zhan's husband, Xue Donghua and their son, Andrew, are released from custody and are allowed to return to the U.S.

April 8, 2001 -- American scholar Wu Jianmin, a writer and U.S. citizen from New York, is detained, also on suspicion of spying for Taiwan.

March 28, 2001 -- Gao Zhan is accused of "accepting money from a foreign intelligence agency and participating in espionage activities in China."

May 15, 2001 -- The Chinese government formally charges Li Shaomin with spying for Taiwan.

July 14 2001 -- A Beijing court convicts Li Shaomin of espionage and sentences him to deportation.

July 24, 2001 -- A Beijing court convicts Gao Zhan and Qin Guangguang, both Chinese-born scholars with U.S. permanent residency, of spying, and sentences them to 10 years in prison.

July 24, 2001 -- The White House calls for the release of Gao Zhan and Qin Guangguang on humanitarian grounds.

July 25, 2001 -- Li Shaomin is expelled from the Chinese mainland and returns to the U.S.

July 26, 2001 -- China releases Gao Zhan after granting her and Qin Guangguang medical parole.

July 30, 2001 -- Li Shaomin is allowed to enter Hong Kong after five hours of interrogation by Hong Kong immigration authorities.

August 1, 2001 -- Chinese authorities formally charge U.S. academic Wu Jianmin with endangering national security.