BEIJING: At least four Tibetans may have been killed and 30 others hurt when Chinese police fired on crowds protesting the expansion of mine operations blamed for environmental damage, a report said Saturday.

The shooting occurred August 17 in a remote region of southwestern China`s Sichuan province with a history of seething unrest involving the area`s Tibetan community, US-based Radio Free Asia said.

Quoting exiled Tibetans with sources in the region, the report said the confrontation began on or around August 13 when a group of Tibetans went to the Palyul county government headquarters to protest.

They complained that stepped-up Chinese gold-mining operations had brought large numbers of people and heavy machinery to the area, damaging farmland and the local grassland habitat, it said.

County officials rejected the accusations and had the demonstrators detained, touching off a steadily escalating confrontation that lead to the August 17 shootings.

Some of those injured were severely hurt, it said. Two police officers also were reportedly injured that day.

It quoted a county government official saying negotiations were under way to settle the dispute.

Local police denied knowledge of any confrontation when reached by AFP via phone. Calls to the county government went unanswered.

Palyul is in the Garze Tibetan Autonomous prefecture, one of many areas of the Tibetan plateau hit by widespread anti-Chinese rioting in March 2008 that was met with a massive security clampdown.

BDST: 1435 HRS, August 28, 2010