Chinese President Hu Jintao, forced to abandon a G-8 summit in Italy by ethnic violence in restive Xinjiang, said that maintaining social stability in the energy-rich region was the “most urgent task”, state television reported on Thursday.

Hu described Sunday’s riots in Urumqi, where 156 people were killed and 1,080 wounded in clashes between Muslim Uighurs and Han Chinese, as a “serious violent crime elaborately planned and organised by ‘three forces’ at home and abroad”, an apparent reference to religious extremists, separatists and terrorists.

Hu, also the Communist Party chief, told the decision-making Politburo late on Wednesday that local authorities should “isolate and deal a blow to the small group” of rioters and to “unite and educate the majority” of Uighurs.

Foreign Ministry spokesman Qin Gang shrugged off Turkey's call for the UN Security Council to discuss ways of ending the violence, saying Xinjiang was an internal affair.

Thousands of Chinese troops took up position in the riot-damaged streets of Urumqi in a show of force aimed at stifling ethnic violence.

State television showed Zhou Yongkang, China's top official in charge of security, and Public Security Minister Meng Jianzhu, reviewing camouflaged troops in Urumqi. Meng and Zhou were active in the crackdown on Tibetan areas after widespread demonstrations there last year.

Some residents worried about how the two sides could ever co-exist again.