The United Nations' most senior human rights official has urged China to address deep-rooted frustrations that have led to desperate forms of protest by Tibetans, including some 60 self-immolations since March 2011.
Navi Pillay, UN High Commissioner for Human Rights, called on the Chinese authorities to respect Tibetans' rights to peaceful assembly and expression and release anyone detained for exercising those rights.
She said social stability in Tibet would never be achieved through heavy security measures and suppression of human rights.
Ms Pillay also urged Beijing to allow independent human rights monitors to visit Tibet and lift restrictions on media access to the region.
Reuters reports China has branded the self-immolators "terrorists" and criminals and accused the exiled Tibetan spiritual leader, the Nobel Peace Prize-winning Dalai Lama, of inciting them.
The UN official said she recognised Tibetans' intense sense of frustration but urged community and religious leaders to use their influence to help prevent people from setting themselves on fire.
The victims include seven Tibetans who set fire to themselves in the past two weeks in protest against what they said was repressive Chinese rule in the Himalayan region.
Arrests, disappearances and curbs on the cultural rights of Tibetans persist, she said.
Cases have included a 17-year-old girl said to have been severely beaten and sentenced to three years in prison for distributing flyers calling for Tibet's freedom and the return of the Dalai Lama, she said.
Others had been sentenced to four to seven years for writing essays, making films, or distributing photos of events in Tibet outside China, Ms Pillay added.