His voice shaking - either with fear or emotion - the lama explained why he felt greater pressure than at any time since he started to head his monastery.

"I am worried. China is so big. Tibetans are so few. We cannot possibly win. No good can come of this for Tibetans."

The lama has good reason to be concerned. The fragile harmony between Tibetan and Han Chinese communities is being ripped apart all around him. His small monastery - nestling high in the mountains of northern Sichuan - is in the region that has experienced the worst violence outside of Lhasa.

According to overseas Tibetan groups, more than a dozen protesters have been killed in Aba county. It is difficult to verify, but the tension is palpable.

As the unrest has spread, so has the security cordon. The fragile-looking lama now finds his remote monastery - hundreds of miles from the initial protests - on the edge.

"Three officials came up from the town to see me today. They told me we must not protest like the other monasteries or we would be closed off," he said.

In the past two days several bigger monasteries in this area (which cannot be named to protect the sources) have been locked down. Roads in almost every direction are punctuated by police checkpoints. Government officials, park rangers, bank managers and other administrators have been ordered to maintain a 24-hour operation.

"We have to work overtime tonight because the Dalai Lama is trying to split our country," one Tibetan park ranger grumbled to a colleague.

Until last week this area - at more than 3,000 metres (10,000ft) altitude - was a stopping point on the tourist trail. The nearby highway 213 passes through some of the most stunning scenery in China, past many of Tibetan Buddhism's most famous monasteries.

Today, however, the roads are closed. Drivers have been warned to stay away and all the talk is of the baoluan - unrest - gripping neighbouring areas.

Route 213 has become a corridor of unrest. Locals said there were demonstrations yesterday in Ruoergai and Langmusi, where monks held up Tibetan flags and shouted support for the Dalai Lama. Further north police have broken up rallies in Luqu, Xiahe and Hezou in recent days.

What is going on inside the widening security zone is becoming harder to find out as the police add roadblocks, expel foreigners, warn locals to stay away and bring in truckloads of armed riot police.

At the secluded monastery it is at first hard to understand why the Tibetan community would want to rebel. Farmers say their incomes have risen. Many are building big houses. Last year the government built a new road. But there is frustration at the heavy-handed political controls they must live under.

Monks must undergo patriotic education campaigns. There are restrictions on the age at which monasteries can enrol apprentices. The Chinese flag must fly from the monastery roof and Communist posters have to be hung on the walls. "Have the same heart as the party. Follow the same direction as socialism. Be grateful and dedicate yourself to the motherland," reads one near the entrance.

Toughest of all for the monks to bear is the order to renounce the Dalai Lama, their spiritual leader.

"They tell me I must renounce the Dalai Lama. When I go to public meetings that is what I have to say. But in my heart I don't believe the words from my mouth," said the lama.

"We do not have freedom of worship. We don't have enough human rights. Deep down I support those who demonstrate peacefully, but violence is very bad. It doesn't help."