The London-based Free Tibet Campaign said police opened fire on hundreds of Buddhist monks and lay people who had marched on local government offices to demand the release of two monks detained for possessing photographs of the Dalai Lama, Tibet's exiled Buddhist leader.
Xinhua made no mention of deaths or injuries among protesters, but said a "riot" had flared up Thursday night outside government offices in the Garze Tibetan Autonomous Prefecture high in the mountains in Sichuan province along the border with Tibet.
It said the official was "attacked and seriously wounded," and said police were "forced to fire warning shots and put down the violence." No other details were given.
The report indicates continuing unrest in Tibetan areas despite a massive security presence imposed after sometimes violent anti-government demonstrations broke out last month in Tibet's capital Lhasa and neighboring provinces.
Late last month, Xinhua reported that protesters in Garze attacked police with knives and stones, killing one officer.
Matt Whitticase, spokesman for the London-based Free Tibet Campaign, said the incident originated at the Tonkhor monastery in Garze with government attempts to enforce a new "patriotic education campaign" - a program of ideological indoctrination blamed for stirring deep resentment among monks. The campaign demands that monks denounce the Dalai Lama, the spiritual leader of Tibetan Buddhism who fled to India amid a failed uprising against Chinese rule in 1959.
Whitticase said the chief monk, Lobsang Jamyang, refused to allow a government team to enter on Wednesday, but they returned Thursday with a force of about 3,000 paramilitary troops. The two monks, Geshi Sonam Tenzing and Tsultrim Phuntsog, were detained after photos of the Dalai Lama were found among their belongings.
Soon afterward, the monastery's 370 monks marched on local government headquarters to demand their release, joined by about 400 lay people, Whitticase said. The group left after being told the two monks would be freed at 8 p.m., but returned after officials reneged. Along the way, they were confronted by troops at a road block, who opened fire on the crowd, Whitticase said.
Whitticase provided the names of six of the eight people reportedly killed, who included at least three women and one monk. He said information on the incident had been relayed by a monk at a Tibetan Buddhist monastery in southern India, who received it from anonymous contacts in Garze.
Stepped-up patriotic education has been ordered as part of a crackdown on dissent following deadly riots in the Tibetan capital, Lhasa, on March 14, in which authorities say 22 people died. Other reports say up to 140 people were killed in the protests and ensuing crackdown.
Beijing has accused supporters of the Dalai Lama of orchestrating the violence, a charge the 1989 Nobel Peace Prize winner has repeatedly denied.
Authorities earlier this week said they plan to put rioters on trial and reopen Tibet to foreign tourists by May - a tight timetable that would allow the government to put the issue behind it ahead of the August Beijing Olympics.
Both Tibet and Tibetan communities in three neighboring provinces where the protests spread, however, remain largely closed to foreign journalists. Outside of Tibet, police turned away foreign reporters at roadblocks leading into Tibetan areas, saying they were unsafe for travel.
A state media report on Friday said officials in Tibetan areas were being forced into political study sessions in a bid to make sure Beijing's dictates are followed.
"The numerous party members and grass-roots officials must further launch education in opposing separatism and preserving the unity of the motherland," the state-run Xinhua News Agency said, citing a notice from the party's powerful Organization Department, which oversees personnel issues.
Communist troops marched into Tibet in 1950 and Beijing strengthened its hold on the region after the Dalai Lama fled in a failed uprising against Chinese rule in 1959.