Chinese authorities locked down the Tibetan capital of Lhasa on Saturday after several days of protests by Buddhist monks, with the Dalai Lama's exiled Tibetan government saying at least 30 Tibetans were killed in a violent crackdown the day before.

Witnesses inside Lhasa told media agencies that a massive military presence was out on the streets on Saturday to enforce a curfew declared by the Chinese government in Tibet after violence erupted on the fifth day of sporadic and largely peaceful protests.

A Tibetan monk keeps watch after Chinese riot police blocked a road to the Labrang Monastery in Xiahe, Gansu province, where clashes between monks and security forces were reported Saturday.
(Andy Wong/Associated Press)

Tourists were ordered out of the city, the Associated Press reported.

The protests, which began Monday on the anniversary of a 1959 uprising, were the largest demonstrations in nearly two decades against Beijing's rule over Tibet.

Radio Free Asia reported Friday that troops, using both live ammunition and tear gas, fired on crowds of protesters, who had been setting fire to cars and shops in Lhasa.

Meanwhile, clashes were reported Saturday between monks and security forces in the town of Xiahe, in Gansu province.

The Tibetan government-in-exile, based in northern India, said it had information that as many as 100 Tibetans may have been killed by Chinese authorities. The figures could not be independently verified.

China's official Xinhua news agency put the death toll from Friday's unrest at 10, reporting that most of the victims were shopkeepers. China's government in Tibet accused the Dalai Lama's supporters of inciting the unrest.

in the Nepalese capital of Kathmandu, police broke up a protest by 200 Tibetans, beating them with bamboo batons and arresting at least 20.

In 1951, the Chinese army occupied Lhasa and forced Tibet to sign a treaty with Beijing recognizing China's rule. Under the treaty, Tibet became a "national autonomous region" ruled by a Chinese commission, with the Dalai Lama as a figurehead ruler.

The violence poses difficulties for a communist leadership that has looked to its hosting the Summer Olympics as a way to recast China as a friendly, modern power.

With files from the Associated Press