Tenzin Delek Rinpoche, 65, a Tibetan monk and prominent political prisoner, died in Chinese captivity on Sunday. In 2002, he was arrested and imprisoned on a bombing charge his supporters claim was wrongful. The United States, European Union, and international human rights organizations all pushed for his release.

Originally, he was slated for the death sentence, but thanks to pressure from international groups, the Chinese government commuted his sentence to twenty years.

In addition, Tenzin Delek’s supporters claim that he was in ill-health and required medical parole to seek treatment.

Under Chinese law, if an inmate has served seven years and has chronic health conditions, he is permitted to leave on medical parole.

However, the humanitarian concerns about Tenzin Delek’s imprisonment were ignored by the Chinese government.

“The fact that he was not even allowed medical parole and last wish of followers to see him reflects continuing hardline policies of the Chinese government,” Lobsang Sangay, the head of the India-based Tibetan government in exile, said. “Such mistreatment will only create more resentment among Tibetans.

Members of China’s Public Security Bureau admitted to the press that Tenzin Delek had died but refused to give any further details.

Sources close to Tenzin Delek say that his body has not yet been returned to his family.

Some groups are reporting that Chinese troops are moving into the area where Tenzin Delek lived to deter any possible protests.

“We fear for the lives of the Tibetans inside Tibet who are deeply affected by the death of their beloved Buddhist teacher Tenzin Delek Rinpoche. With news of armed Chinese troops moving into the local area, there is a heightened risk of a violent crackdown,” Tenzin Dolkar, executive director of Students for a Free Tibet, said.

“World leaders must publicly condemn the Chinese government for the death of an innocent Buddhist monk and human rights defender and take concrete action to protect the lives of Tibetans in Tibet,” his statement continued.

“His death is in every sense a political murder – a long, drawn out execution of a Tibetan hero who was a religious leader, environmentalist and rights advocate. We condemn the Chinese government for the murder of Tenzin Delek Rinpoche,” the statement also said.

China first invaded and occupied Tibet under Mao Zedong in 1950. The mountainous nation had some measure of autonomy until 1959, however when the Chinese Communists dissolved the country’s government and sent the Dalai Lama—Tibet’s religious leader and an important figure in Buddhism—fleeing into exile.