BEIJING - Attackers killed at least 31 people Thursday when they ploughed two vehicles into a market and threw explosives in the capital of China's Xinjiang region, in what authorities called the latest "severe terrorist incident" to hit the Muslim Uighur homeland.
More than 90 people were also wounded when two off-road vehicles drove into a crowd in Urumqi, with one of them exploding, the regional government's Tianshan web portal said, in an attack with echoes of a fiery car crash in Tiananmen Square last year.
China has seen a series of incidents in recent months targeting civilians, sometimes far from Xinjiang itself, that authorities have blamed on separatists from the region.
Pictures posted on Sina Weibo, a Chinese equivalent of Twitter, showed victims lying in a tree-lined street, as others sat on flimsy stools.
Flames rose in the background, while other images showed smoke billowing over market stalls behind a police roadblock. None of the photographs could immediately be verified.
Chinese President Xi Jinping pledged to "severely punish violent terrorists", maintain a "strike first" policy and "crack down on them with a heavy fist", state broadcaster CCTV said.
Beijing says it faces terrorism from a violent separatist movement in Xinjiang, driven by religious extremism and foreign groups.
Critics point to economic inequality and cultural and religious repression of Uighurs as drivers of unrest in the vast and resource-rich far western region.
Tianshan described the attack as a "severe, violent terrorist incident".
"Thugs broke through protective metal barrier by driving two vehicles, colliding with the crowd and detonating explosive devices, causing the deaths of 31 people and injuring 94," it said.
A witness at the market told the official news agency Xinhua he heard a dozen "big bangs" during the attack at about 7:50am (2350 GMT Wednesday), when Chinese morning markets are commonly crowded with shoppers seeking fresh groceries.
"I saw flames and heavy smoke as vehicles and goods were on fire while vendors escaped leaving their goods behind," wrote one Weibo poster who said he was less than 100 metres (yards) from the scene.