Tibetans arrested by Chinese security forces have been paraded with placards around their necks indicating their names and alleged crimes such as "separatism", according to photographs published Saturday by the Free Tibet campaign group.

The pictures were taken in the ethnic Tibetan prefectures of Ganzi and Aba in Sichuan province, the Chinese dissident website Boxun.com said Friday, according to the London-based group.

It did not give more specific information on where and when they were taken, Free Tibet said.

These Tibetan-inhabited areas of Sichuan have seen a series of self-immolations by Buddhist monks and nuns in protest over Chinese religious repression.

In one of the photos, armed and helmeted Chinese paramilitary policemen hold monks by the back of their necks, heads bowed and with signs around their necks, as they escort them out of a building.

One of the monks, Lobsang Zopa, has his name written in Chinese on the sign along with the word "separatist", a charge punishable by life imprisonment, according to Free Tibet.

In another photo, pairs of policemen twist the arms of detained civilians behind their backs to make them lower their heads.

A third shows Tibetans on their knees with signs around their necks with their names, written in Chinese, accompanied by the charge "separatist" or "assembling to attack state institutions".

A fourth picture shows an open-topped truck loaded with monks who are bent over with their heads sticking over the side as they are kept in this position by paramilitary forces, again with signs around their necks.

Until at least the 1980s, it was common in China to parade condemned convicts in public in this fashion. If they were sentenced to death, their names were marked with a cross.

Another three pictures, which Free Tibet said it had determined were taken in the town of Aba, show a police checkpoint, a large gathering of security forces and a patrol armed with assault rifles.

China, which claims to have "peacefully liberated" Tibet in 1951, closely monitors the region and neighbouring provinces of the Tibetan plateau.

'First immolation attempt' in China's Tibet: campaigners
Beijing (AFP) Dec 2, 2011 - A former Buddhist monk has set himself alight in Tibet, a campaign group said Friday, citing Tibetan exiles in India and calling it the first such protest in the vast autonomous region of southwestern China.

The report from the International Campaign for Tibet (ICT) follows a series of self-immolations by Buddhist monks and nuns in Tibetan-inhabited regions of the country, where ethnic Tibetans have long chafed against Chinese rule.

The former monk, said to be in his 40s, is reported to have survived and been taken to hospital in Tibet's Changdu prefecture.

"Reports that have been micro-blogged and uploaded on Facebook accounts in Tibetan indicate that the Tibetan, named as Tenzin Phuntsog, survived and has been hospitalised," said the ICT in a statement.

"If the accounts that have emerged so far are correct this would be the first self-immolation to occur in the Tibet Autonomous Region," the ICT said.

China's state-run Xinhua news agency confirmed late Friday that Phuntsog -- who it identified as a 42-year-old farmer -- was in stable condition.

He attempted suicide after being caught Wednesday for illegally chopping down trees, it said citing local officials who called Phuntsog "eccentric" for brandishing a knife at a forest ranger he suspected of tipping off authorities.

But the ICT said the former monk was reported to be from a monastery that some sources said was under lockdown following rumours of a bomb blast at a local government building on October 26.

Police in Changdu told AFP earlier that they were unaware of the incident, which was reported to have occurred on Thursday.

Xinhua said Phuntsog set himself ablaze after pouring gasoline over his body, and was stopped by two workers nearby who doused the fire with an extinguisher from their motor vehicle.

Rights groups say nine monks and two nuns have have set themselves on fire this year in Sichuan province, which borders Changdu, to protest against religious repression of Tibetan Buddhists, and that at least seven have died.

Many were from Kirti monastery in Sichuan's Aba county, which has been under virtual lockdown since a young monk named Phuntsog set fire to himself and died in March, sparking mass protests there.

Many Tibetans in China accuse the government of enacting religious repression and of eroding their culture, as the country's majority Han ethnic group increasingly moves into historically Tibetan areas.

China rejects this, saying Tibetans enjoy religious freedom and pointing to huge investment in development that it says has brought modernisation and a better standard of living.