Rebiya Kadeer, head of the Uighur American Association, said that security forces were rounding up many people ahead of the flame's circuit of the western region late next month.

"The Chinese authorities have been heavily cracking down on the Uighurs in order to bring the torch through East Turkestan," Kadeer said, using the Uighur term for the region.

"We have learned that many Uighurs are being detained and arrested by the Chinese authorities to prevent their peaceful protests in relation to the torch," she said in an e-mailed answer to queries.

Leaders of Xinjiang's Uighurs, a Muslim central Asian people who have long chafed under Beijing's control, accuse China of harsh oppression and policies that they say are aimed at extinguishing their culture.

"I am opposed to the torch passage because it comes with severe repression of the Uighur people," she said. Kadeer's comments follow allegations Saturday by another overseas Uighur leader that more than 10,000 people were believed to have been rounded up in Xinjiang over the past four to five months.

Kadeer, who spent six years in a Chinese jail from 1999-2005 and now lives in exile in the US, also repeated her charge that China fabricated recent claims that it broke up Xinjiang-based terror cells targeting the Olympics.