The attackers also threw explosives from the car as they plowed through shoppers early Thursday morning. The market was crowded with senior citizens who had just finished their morning exercises and were eating breakfast at the market.
The Ministry of Public Security has called the attack a "violent terrorist incident."
The region is home to the Muslim Uighur minority, who have had a history of tensions with the Han Chinese. While authorities have not discussed the ethnicity of the attackers, witnesses at the scene have said that they were Uighurs. Witnesses also say that the cars had no number plates, but had two small black flags carrying writing in the local Uighur language.
According to the Xinhua news agency, Chinese President Xi Jinping pledged to severely punish the "terrorists" and spare no efforts in restoring normalcy in the region.
"At close to 8 this morning, there were multiple explosions at the morning market near the Cultural Palace in Urumqi," a user called Paike Luotuoci posted on the Chinese microblogging service Sina Weibo. "I was less than 100 meters from the scene and I could see flames, heavy smoke. There were vehicles and goods burning. Vendors left their goods behind and fled."
"I saw flames and heavy smoke as vehicles and goods were on fire while vendors escaped leaving their goods behind," another witness wrote online, who claims he was less than 100 yards from the scene.
Urumqi and the region have seen their fair share of ethnic violence as Uighur separatists complain about Chinese restrictions on the Uighurs' religion, language and freedom of movement. China reestablished control of the region in 1949 after crushing the short-lived Uighur state of East Turkestan. Since then there has been an influx of Han Chinese into the region, which the Uighurs fear could impede their way of life and culture.