Dozens of civilians were killed or injured in a terrorist attack in northwest China's Muslim-majority Xinjiang region, state-run Xinhua News Agency reported Tuesday. A gang armed with knives attacked a police station and government offices on Monday morning in Elixku, a township in Kashgar Prefecture of Xinjiang Uygur Autonomous Region, and some moved on to the nearby Huangdi Township, attacking civilians and smashing vehicles as they passed, the report said. Dozens of Uygur and Han ethnic civilians were killed or injured, the local police said. Police officers at the scene shot dead dozens of members of the mob. The report also said 31 cars were vandalized, including six which were set on fire. Initial investigation showed that it was a premeditated terror attack. About 41.5 percent of Xinjiang's 21 million population are Uygurs, a largely Muslim ethnic group. Located in a volatile region, Xinjiang has been battling separatism, extremism and terrorism since China took control of the area in 1949. During its most deadly unrest in decades, 197 people were killed and about 1,700 others injured in the July 2009 riot.