The U.S. Commission on International Religious Freedom, a U.S. government-backed watchdog body, said that the riots were the products of long-standing ethnic tensions.
"Chinese policies are the source of Uighur distrust and resentment, and violate internationally guaranteed freedoms China has pledged to uphold," commission Chairman Leonard Leo told McClatchy Newspapers.
Chinese officials dispute this.
"The nature of the riot is neither an ethnic nor a religious issue, but a grave and a violent criminal incident plotted and organized by the outside forces of terrorism, separatism and extremism," Vice Foreign Minister He Yafei said Wednesday at a news briefing.