2010 Nobel Peace Prize laureate Liu Xiaobo died in Chinese custody at age 61 on Thursday, reportedly of multiple organ failure due to liver cancer.

His treatment is a devastating indictment of China’s human rights abuses and should bring increased international attention to how the authoritarian regime in Beijing silences dissenters.

As the New York Times observes, Liu was silenced and kept under guard even as he was dying in the First Hospital of China Medical University. His illness was not acknowledged by the Chinese government until late June. His wife was held under house arrest and kept quiet until after that belated government announcement, when she was able to post a video message that said, “Can’t operate, can’t do radiotherapy, can’t do chemotherapy.”

“People from all walks of life—friends, strangers, young people—have been outraged to hear that someone with terminal cancer was kept locked up till he died,” former Beijing professor of literature Cui Weiping told the New York Times. The paper observes that Liu is the first Nobel laureate to die in custody since pacifist Carl von Ossietzky died in a Nazi prison in 1938.

“His supporters and foreign governments had urged China to allow him to receive treatment abroad, but Chinese authorities insisted he was receiving the best care possible for a disease that had spread throughout his body,” reports the Associated Press. 154 Nobel laureates gave their support to his request for overseas medical treatment.

Liu’s career of activism included negotiating the safe departure of hundreds of Tiananmen Square protesters who would probably have been killed by the Chinese Communist regime without his intervention. That got him thrown in jail for a while, and since he went back to work seeking freedom for imprisoned Tiananmen Square demonstrators as soon as he got out, he ended up in a labor camp, where he met his wife Liu Xia.

In 2009, Liu joined over 300 other activists in drafting a manifesto calling for free speech, inalienable human rights, equality before the law, and multi-party republicanism in China. For this he was charged with the “major crime” of “inciting subversion of state power” and given his fourth and final prison sentence.

His Charter 08 had gathered over 10,000 signatures at the time of his arrest, at which point the tyrants of Beijing yanked it off the internet. Writing at U.S. News, his lawyer Jared Genser recalls then-President Hu Jintao remarking that his regime threw Liu, the first and most famous signatory to the charter, in prison to “cut off the head of the snake.”

Genser writes that he was honored to attend Liu’s 2010 Nobel ceremony in Oslo, at which the prize was awarded to an empty chair. Liu Xia has said her husband wept and said the prize should be given to all victims of the Tiananmen Square crackdown when she visited him in prison.

“Despite the tragedy that Liu’s freedom has come from his death, it is clear today that the Chinese government has lost,” Genser declares. “Liu’s ideas and his dreams will persist, spread, and will, one day, come to fruition. And his courage and his sacrifice for his country will inspire millions of Chinese activists and dissidents to persevere until China has become the multi-party democracy that Liu knew to his core was within its people’s grasp.”

“We find it deeply disturbing that Liu Xiaobo was not transferred to a facility where he could receive adequate medical treatment before he became terminally ill. The Chinese government bears a heavy responsibility for his premature death,” the Nobel committee said in a statement released on Thursday.

“He was truly a prisoner of conscience and he paid the highest possible price for his relentless struggle,” the Nobel Committee added.

Both Germany and the United States enthusiastically offered to provide such treatment, but were refused by the Chinese government with a mixture of assurances that he was receiving the best possible care from Chinese doctors, and angry demands that other nations stay out of China’s internal affairs. China’s claims that he was too ill to travel were disputed by the few foreign doctors given access to him.

Human Rights Watch, which gave Liu its 2010 Alison Des Forges Award for Extraordinary Activism, said his death “lays bare the Chinese government’s ruthlessness toward peaceful proponents of human rights and democracy.”

“Even as Liu Xiaobo’s illness worsened, the Chinese government continued to isolate him and his family, and denied him freely choosing his medical treatment. The Chinese government’s arrogance, cruelty, and callousness are shocking—but Liu’s struggle for a rights-respecting, democratic China will live on,” said HRW China Director Sophie Richardson.

Liu’s work is not done, and China has a great deal to answer for in the way it has treated other activists. The South China Morning Post coincidentally published a devastating report earlier this week on China’s harsh treatment of human rights lawyers swept up in the “709 crackdown” of 2015. The lucky ones had their lives destroyed and were placed under pervasive surveillance. Other victims were jailed and tortured with everything from sleep deprivation and “painful stress positions” to electric shocks.