Yu, a Christian writer and friend of jailed Nobel Peace Prize winner Liu Xiaobo, said arrests and torture became a common occurrence after Liu was awarded the prize in 2010, Britain's The Guardian newspaper reported Thursday.
Yu said Chinese security officials stripped him, beat him unconscious and threatened to post naked pictures of him online.
He and his family arrived in the United States last week.
The 38-year-old writer, best known for his book "Wen Jiabao: China's Greatest Actor," said he angered authorities by writing a biography of Liu Xiaobo.
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