Before boarding a flight to Hong Kong, he was detained at immigration. His assistant was also detained. Ai's studio has been surrounded by plainclothes police and is thought to have been raided. No one can get in touch with Ai and posts about him on Weibo, a Chinese microblog similar to Twitter, are being deleted.
Asked about Ai, an airport police spokesman said: "I do not have the obligation to tell you the information. You may have got your information wrong; even if it is right, you have to go through certain procedures to make inquiries, not just make a phone call."The Guardian reports that Ai had previously been relatively free from this type of harassment because of both his family and his international reputation.