Nobel Peace Prize laureate Liu Xiaobo, China's most prominent political prisoner, has died of multiple organ failures, Chinese officials announced Thursday. He was 61.

His supporters and foreign governments including the United States had urged China to allow him to receive treatment abroad, but officials insisted he was receiving the best possible care.

Friends of Liu had risked detention earlier Thursday by visiting the First Hospital of China Medical University in northeast China where he was being treated under guard for advanced liver cancer.

“Liu Xiaobo is on his deathbed,” said writer and activist Wen Kejian, the Guardian reported earlier. “Although we know the patient and his family are suffering, we are praying that Xiaobo can hold on for a few more days."

Liu was convicted in 2009 of inciting subversion for his role in the “Charter 08” movement calling for political reform and was sentenced to 11 years in prison. He was awarded the Nobel Peace Prize a year later while serving his sentence.

Liu, a former professor, had helped negotiate with the military for the safe passage of students during the 1989 Tiananmen Square protest.

On Wednesday, White House spokeswoman Sarah Huckabee Sanders called on the Chinese government to grant Liu full parole and release his wife, Liu Xia, from house arrest.

She also called on Chinese authorities to "provide them the protections and freedoms, such as freedom of movement and access to appropriate medical care consistent with Chinese constitution, legal system, and international commitments."

Secretary of State Rex Tillerson released a statement Thursday: "In his fight for freedom, equality, and constitutional rule in China, Liu Xiaobo embodied the human spirit that the Nobel Prize rewards. In his death, he has only reaffirmed the Nobel Committee’s selection‎."

Geng Shuang, a Chinese foreign ministry spokesman, said: “We hope relevant countries can respect China’s judicial sovereignty and refrain from interfering in China’s internal affairs under the pretext of an individual case.”

Contributing: the Associated Press

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