Liu, awarded the Nobel in 2010, has been detained since 2008 for a manifesto calling for the end of single-party rule in China. He was sentenced to 11 years in for allegedly inciting subversion of state power, the British newspaper The Daily Telegraph reported Friday.
International Committee of Support to Liu Xiaobo said Liu is the only Nobel laureate currently in prison.
"Unfortunately, the sentencing to 11 years in prison seems to be forgotten slowly but steadily outside China," the group, which includes Shirin Ebadi, Jody Williams, Mairead Maguire, Betty Williams and Desmond Tutu, said in a release.
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