The leader of a U.S.-based Uighur organization says this week's violence in the restive northwest region of Xinjiang is the result of “oppressive” Chinese policies against ethnic minorities.

China's foreign ministry accused separatists and violent terrorists in the heavily ethnic Uighur region of attacking civilians with knives on Tuesday, in violence that it says killed at least 20 people — including seven Chinese policemen and nine of the assailants.

But Alim Seytoff, the president of the American Uighur Association, disputes that account, telling VOA the violence was not terrorism, but the result of a harsh crackdown on ethnic minorities.

“It's the Chinese government security forces who have been provoking the Uighurs to fight back. It's the Chinese government policies, which are aimed at eliminating the language, culture, religious beliefs, and values of the Tibetans and Uighurs.”

Seytoff said Chinese anti-riot squads have routinely harassed, beaten and detained Uighurs ever since the 2009 unrest that left nearly 200 people dead in the regional capital of Urumqi.

Eight people were also killed in a shoot-out with police in December, during what Beijing described as the rescue of two herdsmen who had been kidnapped by “terrorists.”

The Chinese government has blamed the violence in the resource-rich region on Islamist extremists.

But exile groups say the Turkic-speaking Uighurs are rioting over longstanding grievances. Uighurs say they are economically and culturally disadvantaged, and face widespread discrimination resulting from a massive influx of ethnic Han Chinese into the region.