China has deployed thousands of troops in Urumqi, capital of the far western Xinjiang region, in an effort to restore calm between the city's ethnic Uighurs and Han Chinese.
Clashes between the groups have paralysed the city since Sunday when a street protest by Uighur demonstrators turned into some of the bloodiest ethnic violence seen in China in years. Chinese officials say the violence has left more than 150 people dead and around a thousand injured.
More than 1,000 people are reported to have been arrested and on Wednesday a senior official warned that anyone found guilty of murder would be executed. "To those who committed crimes with cruel means, we will execute them," Li Zhi, the Communist party chief for Urumqi, told reporters.