Tibet's Chinese governor says rioters in the capital of Lhasa will face harsh punishment if they do not turn themselves in before a midnight (1600 UTC) deadline.
Speaking with reporters Monday in Beijing, Qiangba Puncog insisted that Chinese authorities had not used deadly force against protesters. He also said that those who surrender and provide information about others involved will receive leniency.
Qiangba said that during violent protests against Chinese rule in Lhasa last Friday, rioters either burned or hacked to death 13 innocent civilians.
Tibet's government in exile, based in India, has estimated at least 80 Tibetans were killed.
No death toll figures have been confirmed.
Human rights groups say Chinese security forces in Tibet are conducting house-to-house searches in Lhasa, arresting those suspected of taking part in the demonstrations.
Witnesses say there is a heavy military presence in Lhasa, with at least 100 army trucks and many paramilitary troops deployed throughout the city.
Unrest that spilled over into violent demonstrations in Lhasa last week spread to Tibetan communities in other parts of China Sunday.
In neighboring Nepal, police clashed with around 100 Tibetan protesters and Buddhist monks today, arresting about 30 people.
China has controlled Tibet since 1951. The Dalai Lama and thousands of his followers fled from Tibet to India in 1959, during a failed revolt against Chinese rule. China denounces the Dalai Lama as a crusader for independence, but he says he has campaigned for nothing more than true autonomy for his homeland.