China on Tuesday blamed Buddhist monks for causing unrest in a Tibetan region, accusing them of disrupting social order and defaming their religion.

The foreign ministry refused to confirm allegations two Tibetans were killed in a security crackdown at the Kirti Monastery in the southwestern province of Sichuan, but gave the clearest official acknowledgement yet of unrest there.

"In recent days, a small number of monks in Kirti Monastery in Aba county, Sichuan have disrupted social order and disobeyed Tibetan Buddhist rules," foreign ministry spokesman Hong Lei told reporters.

They have "disrupted local normal order, defamed the image of Tibetan Buddhism and harmed the feelings of Buddhist followers."

According to the US-based International Campaign for Tibet, unrest in the Chinese region erupted in March when a young monk set himself on fire and died in an apparent anti-government protest.

On Thursday last week, paramilitary police raided the monastery and took away more than 300 monks. Authorities also started a re-education programme at Kirti, the group said.

Police also beat a group of laypeople who had been standing vigil outside the monastery, leading to the deaths of two Tibetans aged in their sixties, ICT said.

"People had their arms and legs broken, one old woman had her leg broken in three places, and cloth was stuffed in their mouths to stifle their screams," an exiled Kirti monk was quoted as saying by the rights group.

The remote, mountainous region has now been closed to foreigners.

Tensions run deep in Tibetan areas of China, where many Tibetans accuse the government of trying to dilute their culture, and cite concern about what they view as increasing domination by China's majority Han ethnic group.

That tension erupted in violent demonstrations in March 2008 in Tibet's capital Lhasa, which then spread into neighbouring Tibetan areas of China, including Aba.

Hong insisted the re-education programme was needed to fulfill China's "religious freedom" policies.

It was also necessary to "strengthen the administration of religious affairs in accordance with the law and maintain normal religious order," he said.

The Tibetan government-in-exile in the northern Indian town of Dharamshala said in a weekend statement that it was "deeply concerned" by the "grim situation at the Kirti Monastery".