China has deployed thousands of extra troops and paramilitary forces across Tibetan regions to head off unrest after several recent protests against government by Beijing.

The Communist Party is increasingly nervous that anger against Chinese rule — that has simmered among Tibetans since widespread demonstrations in March and April last year — could erupt into renewed violence, particularly over the Tibetan New Year, or Losar, on February 25.

The build-up of security in Tibetan areas comes as Hillary Clinton, the new US Secretary of State, arrives in Beijing for a weekend of talks with Chinese leaders. The show of force is likely to complicate talks, which are expected to focus not only the global financial crisis and climate change but also on human rights and the situation in Tibet.

Columns of army vehicles have been seen clogging narrow mountain roads into Tibetan-populated regions of southwestern Sichuan province in the past few days. Soldiers have been sent out from the Chengdu Military Region — one of seven military commands in China – along with members of the paramilitary People’s Armed Police. Their numbers could amount to as much as two divisions, or as many as 20,000 men, but such numbers could not be confirmed in a country in which all military movements are a state secret.

The troops have even been permitted to carry loaded weapons, a rare and extreme measure for soldiers operating within China’s national borders, local sources said.

In Hongyuan, sources described the troops arriving in large convoys stretching into dozens, sometimes hundreds, of vehicles. One resident said: “The town will be pretty much closed from February 22 because on February 25 the PLA will hold a military exercise here.”

That exercise, in a region that was particularly volatile last year, falls on the day of the Tibetan New Year – a celebration that many Tibetans say they will boycott out of mourning for those killed or jailed after last year’s unrest, in a move has enraged the Chinese authorities.

Hundreds of angry Tibetans rampaged through the streets of Lhasa on March 14 last year, burning offices and shops and killing at least 18 people as they vented their rage against Chinese rule and called for the return of the exiled Dalai Lama.

In several other towns, residents described seeing an increase in troops movements in the past few days. In Aba and Ganze, two other of the most restive regions last year, residents said that army patrols were now taking place around the clock. In Langmusi, on the border between Sichuan and Gansu provinces, squads of paramilitary have filled hotels in the town surrounded by ancient Buddhist temples.

In Litang, where the arrest of a lone monk demonstrator led to a protest this week, people said they had seen about 100 military vehicles on the streets. Local sources said two that Chinese traffic police and one paramilitary had been stabbed to death in the night and police were warning each other not to wear their uniforms after dark.

In Lhasa, the Tibetan capital, pamilitary patrols has been increase from squads of five men to thirteen, moving through the streets both day and night. At night even armoured personnel carriers were to be seen on the streets, residents said, along with numerous military and police vehicles — all driving without their sirens.

Troops have also been deployed around most big monasteries in Tibetan regions and all police in Tibetan areas of Sichuan have been ordered to report for duty until further notice. A platoon of 100 soldiers has been deployed on the Gangtuo bridge the crosses a river on the provincial border between Sichuan and Tibet after reports of an attempt to set off explosives there in the past few days, sources said.

The growing antipathy between ethnic Tibetans and ethnic Han Chinese burst into violence this morning in the town of Nagchu, north of Lhasa. The trouble started with a fight between a Tibetan lorry driver and an ethnic Han Chinese taxi driver and swiftly grew into a street brawl involving hundreds of Tibetans. They shouted slogans demanding the return of the Dalai Lama and set fire to police cars, prompting security forces to open fire. Three people were reported to have been wounded and some 17 detained.

The security clampdown is likely to increase with the approach of the first anniversary of the March 14 riot in Lhasa and the 50th anniversary of the flight into exile of the Dalai Lama after an abortive anti-Chinese uprising that began on March 10, 1959.

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