BEIJING (Reuters) - The Tibetan capital Lhasa braced for more possible confrontation on Saturday after independence protesters challenged China’s rule in the fiercest protests to have rocked the region in two decades.

China accused followers of the Dalai Lama of “masterminding” the uprising, which shatters its carefully-cultivated image of national harmony in the build-up to the Beijing Olympic Games.

Angry crowds in the remote mountain city on Friday attacked government offices, burned vehicles and shops and threw stones at police in bloody confrontations that left many injured, according to Chinese state media reports.

China has said that Tibet’s exiled spiritual leader, the Dalai Lama, engineered what were the biggest protests in disputed region since 1989, a claim he quickly denied.

But while it was unclear whether the clashes would flare or even escalate over the weekend, Beijing has already made it clear that it saw no reason to change its policies in Tibet, where many locals resent a growing Han Chinese presence, especially in Lhasa.

“We are fully capable of maintaining the social stability of Tibet,” the Xinhua news agency quoted an official as saying in a statement repeated across Chinese state media on Saturday.

“The plots by the very few people against the stability and harmony of Tibet run counter to the will of the people and are doomed to fail.”

Chinese authorities were nonetheless also bracing for more possible unrest in Lhasa on Saturday. “Police cordoned off a few downtown sections and are on close lookout for comeback of violence,” the official Xinhua agency said.

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OLYMPIC SHADOW

Already the eruption of popular anger at China’s presence in Tibet has become an international issue likely to shadow Beijing’s preparations for the Olympic Games in August.

U.N. High Commissioner for Human Rights Louise Arbour urged China “to allow demonstrators to exercise their right to freedom of expression and assembly, to refrain from any excessive use of force while maintaining order and to ensure that those arrested are not ill-treated”.

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U.S. ambassador to Beijing Clark Randt told senior Chinese officials on Friday of Washington’s concern. “He took the opportunity, because of what was going on in Lhasa, to urge restraint on the part of the Chinese officials and Chinese security forces,” a U.S. spokesman told reporters.

The demonstrators attacked the office of the region’s official Communist Party-run newspaper and the Xinhua office, the Hong Kong Wen Wei Po reported.

“The Tibet People’s Armed Police Hospital received many injured officers,” it said.

Chinese state media has not reported any deaths, but overseas groups with contacts in Tibet say several people may have died.

A spokesman for the Dalai Lama, contacted in the Indian town of Dharamsala, a centre for Tibetan exiles, said of the Chinese allegation against “the Dalai clique”: “This is absolutely baseless and his holiness has made his stand very clear.”

The Dalai Lama has in recent years called for limited autonomy for Tibet, but some Tibetans demand full independence.