BEIJING (REUTERS).- Chinese police said a company controlled by artist Ai Weiwei had evaded a "huge amount" of taxes, Xinhua news agency reported on Friday, the first indication of the "economic crimes" behind his detention, which has triggered an international outcry. Ai's sister, Gao Ge, said his family had not been officially notified of the tax accusations, which she said were another unfounded effort by the police to justify holding Ai.

Supporters say he is the victim of a crackdown on dissent.

The Beijing Fake Cultural Development Ltd., which has helped produce Ai's internationally renowned art and designs, "was found to have evaded 'a huge amount' of tax" and also to have "intentionally destroyed accounting documents," Xinhua said, citing unnamed police. The brief report also said Ai has been "under residential surveillance," a kind of detention that usually means detainees are confined to their homes. But Ai has been allowed to see his wife only once -- last week -- since he was seized at Beijing's international airport on April 3, igniting an outcry about China's tightening grip on dissent, which has triggered the detention and arrest of dozens of rights activists and dissidents.

Beijing's alarm about dissent intensified after overseas Chinese websites in February spread calls for protests across China inspired by the "Jasmine Revolution" of anti-authoritarian uprisings across the Arab world. Ai's sister said the detained artist Ai was not responsible for the Beijing Fake Cultural Development Ltd. "He's not the company's legally-designated representative, nor is he the chief executive. So even if the company is accused of these crimes, Ai Weiwei should not be detained," Gao said in a telephone interview. "There's been no notification to us or to Lu Qing," she said, referring to Ai's wife. "Again, the authorities are saying one thing to Xinhua to tell the outside world, but they haven't observed any legal procedures to tell us."

The manager of the Fake company, Liu Zhen'gang, and the company accountant were detained about the same time as Ai and also remain in custody, said Gao.

Ai is one of China's best-recognized contemporary artists. His career encompasses protests for artistic freedom in 1979, provocative works in the 1990s and a role in designing the Bird's Nest stadium for the 2008 Beijing Olympics.

Lu Qing could not be reached on Friday night, but said earlier in the week that on Sunday she was suddenly notified by police that she could meet her husband.

She said they were given only 10 or 15 minutes to speak and were instructed not to talk about the case.

"His mental condition was not good. His mood was fluctuating and he was not calm. But physically, he looked normal." Lu said.

"He didn't say anything about his case. I don't even know if he knows the reasons he has been detained."

(Additional reporting by Chris Buckley; Editing by Ron Popeski)

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