Plain clothes security personnel stand guard at a side entrance to a residential compound where Liu Xia, the wife of this year's Nobel Peace Prize winner Liu Xiaobo, is held under house arrest in Beijing on Monday, Oct. 11, 2010. Liu Xia confirmed in a Twitter message that she had been placed under house arrest since Friday. (AP Photo/Ng Han Guan)

Photo by: Ng Han Guan

Plain clothes security personnel stand guard at a side entrance to a residential compound where Liu Xia, the wife of this year's Nobel Peace Prize winner Liu Xiaobo, is held under house arrest in Beijing on Monday, Oct. 11, 2010. Liu Xia confirmed in a Twitter message that she had been placed under house arrest since Friday. (AP Photo/Ng Han Guan)