Ai Weiwei, 53, one of China's most prominent avant-garde artists and human rights activists, poses for a portrait in his Beijing studio on April 25, 2009. Although a show of his art has been “indefinitely postponed” in the People’s Republic of China, a public art piece by Ai, “Circle of Animals/ Zodiac Heads,” is on view at 59th Street and Fifth Avenue in New York from May 2 to July 15. Stephen Shaver/UPI/Newscom
A woman walks past a work by Weiwei, titled ''Cubic Meter Tables'', during a press preview of ''According to What'' at Mori Art Museum in Tokyo in 2009. The exhibition was designed to explore the connections between Ai’s work and its artistic, cultural and historical backgrounds, according to the museum's press release announcing the exhibit. Ren Zhenglai/Newscom
A visitor walks past a work titled ''Dropping a Han Dynasty Urn''. Ren Zhenglai/Newscom
Visitors explore an installation made of 100 pieces of trees titled "Rooted Upon" at the House of Art during the presentation of his exhibition "So Sorry", on October 9, 2009 in Munich, Germany. The exhibit title was taken from many governments' and businesses' apologies for tragedies and wrongdoing. Joerg Koch/AFP/Newscom
An installation titled "Remembering" is seen on the edifice of the House of Art during the exhibition "So Sorry" in Munich, southern Germany. "Remembering" was made of 9000 backpacks to memorialize the 2008 earthquake school age victims of Sichuan, China. They spelled out “She lived happily in this world for seven years,” an epitaph for her lost child uttered by a Sichuan mother. Joerg Koch/AFP/Newscom
Posters are seen scattered over a work at Tate Modern art gallery entitled "Sunflower Seeds" in London, April 9 of this year. The posters followed a "Release Ai WeiWei" sign that went up at the top of the museum in support of the artist. Alice Dunhill/Reuters
The commissioned piece consists of millions of tiny porcelain "seeds," each individually hand-painted in the town of Jingdezhen by over a thousand artisans. Originally planned as an interactive exhibit where visitors could touch and roll in the seeds, the work is a commentary on the global economy and politics behind the phrase "made in China." The flyers were added after WeiWei was arrested. Alice Dunhill/Reuters
Thousands of supporters gathered near the Chinese Consulate in New York on April 17. Protesters carried wooden chairs in solidarity with his earlier work - an installation comprised of 1001 late Ming and Qing Dynasty wooden chairs, shown at Documenta 12 in 2007 in Kassel, Germany. Weiwei has been missing since his arrest on April 3rd in Beijing. Newscom
Weiwei held a piece of debris of his newly built Shanghai studio after it was demolished on Jan. 11 this year. He said the demolition began before dawn without any prior notification and was linked to his political activism. AFP/Newscom
People walk in a street where a stencil, with the words "Who's afraid of Ai Weiwei" has been sprayed in Hong Kong. The EU's foreign policy chief Catherine Ashton expressed alarm at the "deterioration of human rights" in China and called for a halt to arbitrary arrests and disappearances of activists including Weiwei, along with other lawyers and intellectuals. She joined a growing international outcry against the crackdown. Kin Cheung/AP
The International Civil Aviation Organization has called only the second high-level safety meeting in its history after a disastrous year in aviation safety.
ByJoan Lowy, Associated Press
Government and aviation industry officials from dozens of countries are meeting in Montreal this week to try to find consensus on how to keep from losing airliners like the one that vanished without a trace in Asia and another shot down in Eastern Europe.