Chinese President Hu Jintao, forced to abandon a G8 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 the regional capital Urumqi 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, who doubles as 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 riot-damaged streets of Urumqi, a show of force aimed at stifling ethnic violence. But some residents worried about how the two sides could ever co-exist again. Beijing cannot afford to lose its grip on Xinjiang, a vast desert territory that borders Russia, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan and India, has abundant oil reserves and is China's largest natural gas-producing region. Authorities have posted notices in Urumqi urging rioters to turn themselves in or face stern punishment. Li Zhi, Communist Party boss of Urumqi, said he would seek the death penalty for rioters who resorted to murder in a city divided between Uighurs and Han, the country's predominant ethnic group. Those who gave themselves in would be treated more leniently or even avoid punishment, the notices said. Anyone who provided evidence or turned in suspects would be rewarded and protected by the police, they said, providing a hotline.