Protests by monks in Lhasa marking the 49th anniversary of a failed uprising against Chinese rule have turned into more than a week of riots and clashes with security forces.
Protests by ethnic Tibetans have been reported in at least 25 places in Tibet and neighbouring provinces in western China, although not all of them can be independently verified.
The following are the key places and events in the unrest.
Lhasa: The protests began on 10 March, and escalated on 14 March.
The Tibetan government in exile in India says 99 people died in clashes with security forces - including 80 in Lhasa.
Chinese officials say only 13 people died - and they were killed during riots by supporters of the Dalai Lama. Both claims are impossible to verify independently.
Security is reported to be very tight on Lhasa's streets
Businesses belonging to ethnic Han Chinese migrants have been attacked and burnt.
Hundreds of people are reported to have been arrested. Witnesses report a heavy security presence.
Hezuo: Footage emerged on 19 March of Tibetans tearing down Chinese flags to replace them with Tibetan ones.
Machu: A crowd of people reportedly set government buildings on fire the preceding Sunday. The government in exile reported 19 people here in clashes on 18 March.
Gansu protesters tore apart China's flag and raised the Tibetan one
Xiahe: Hundreds of monks rallied here on 14 March. Xiahe is the site of one of Tibetan Buddhism's most important monasteries.
Lanzhou: More than 100 students took part in a sit-down protest on 16 March.
Aba: Riots and casualties reported. China admitted on 20 March that police shot protesters during these clashes, injuring four of them.
Pictures circulated by pro-Tibet activists purportedly show protesters near Kirti monastery who have been killed by security forces.
Garze: Three locals reportedly killed by security forces during clashes on 15-16 March, according to the India-based Tibetan Centre for Human Rights and Democracy
Chengdu: Six-hundred monks flown here from Lhasa to get them out of Tibet, a Chinese source tells the BBC on Sunday.
Taktser: The birthplace of the Dalai Lama. The village has now been cordoned off by security forces.
Tongren: Demonstrations reported at the Rongwo Monastery over the weekend.
Home of the government in exile led by the Dalai Lama. More than 100 Tibetans attempting to march to Tibet were detained by Indian authorities on 14 March.