Ai Weiwei, opens the gate to his home after returning from detention in Beijing, China, Wednesday, June 22, 2011. (Ng Han Guan/AP)

Reuters news service quoted him as saying in English, “I’m sorry I can’t [talk], I am on probation, please understand”

Ai, an outspoken critic of China and a renowned artist whose work is currently touring the United States, was arrested April 3 and has been in detainment on charges of evading a “huge amount” of taxes and intentionally destroying accounting documents. The official Chinese news agency Xinhua said Ai has been released because he displayed a “good attitude in confessing his crimes.” The news agency also reported he promised to repay his back taxes and he has been suffering from ill health.

There is no word on four of Ai’s friends and associates who were picked up shortly after his detainment. Journalist Wen Tao, driver Zhang Jinsong, accountant Hu Mingfen and designer Liu Zhenggang have all been reported missing. Hundreds of other lawyers, activists and intellectuals have disappeared or been detained by authorities since February.

Ai had been publicly keeping track of the disappearing activists on his Twitter stream before his arrest. Though Ai was held on charges of tax evasion, his family and supporters said it was his activism that landed him in trouble.

(Courtesy of Ai Weiwei)