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Reporters Without Borders is worried about Uyghur academic and citizen-journalist Ilham Tohti, who was arrested at his Beijing home on 15 January and has been held at an unknown location ever since.
"We call for Tohti's immediate release in view of the clearly arbitrary and illegal nature of his arrest and detention," Reporters Without Borders said. "It shows how the authorities keep cracking down on the Uyghur community, including those who just freely express their views and inform the world about the disastrous human right situation in the far-west province of Xinjiang."
Reporters Without Borders added: "The violence used by the police during their six-hour search of Tohti's apartment after his arrest is evidence of precisely the kind of persecution that he has been denouncing."
Tohti's wife, Guzaili Nu'er, told foreign news agencies that no fewer than 30 policemen from both Beijing and Xinjiang (which has a large Uyghur population) raided his apartment while he was there. They seized computer equipment, books, Tohti's mobile phones and information about his university students, and refused to say where they were taking him when they left.
Foreign ministry spokesman Hong Lei later said Tohti was accused of "violating the law" and had been "placed under criminal detention."
A teacher at Beijing's Central University for Nationalities and editor of the Uygurbiz.com website, Tohti is a well-known opponent of the government's repressive policies in Xinjiang (officially known as the Xinjiang Uyghur Autonomous Region) and, as result, has been under permanent state security surveillance.
He recently expressed concerned about the growing harassment of the Uyghur population, especially since last October's "incident" involving a car in Beijing's Tiananmen Square, which the authorities blamed on Uyghurs.
Tohti has been subjected to frequent harassment. He was held incommunicado for nearly a month in 2009, at a time of rioting in Xinjiang. Last February, he was prevented from leaving the country and was repeatedly questioned by police at Beijing airport. And in November, policemen reportedly threatened to kill his wife and children.<br/>