The New York Times reports that Contemporary Chinese Art star Ai was arrested at the trial of noted rights advocate:

The artist, Ai Weiwei, best known for helping to design the Bird’s Nest Olympic Stadium in Beijing, said dozens of police officers barged into his hotel room early Wednesday and the rooms of others who had traveled to Chengdu, the capital of Sichuan Province, to testify on behalf of Tan Zuoren, the rights advocate.

The opening session of Mr. Tan’s trial began Wednesday morning and ended hours later without a verdict. The courtroom was closed to the public. Mr. Tan, a well-known writer, has been charged with subversion. He is believed to be on trial because of his role in pushing for an official investigation into widespread school collapses during the Sichuan earthquake last year, and for trying to organize a group event in June to commemorate the 20th anniversary of the massacre of civilians by government forces during the Tiananmen Square protests of 1989.

Chinese Artist Says He Was Barred from Rights Advocate’s Trial (New York Times)