A coordinated attack on an outdoor market in northwest China has left 31 people dead and dozens wounded, prompting promises of a vigorous government response. Bombs and cars were used to inflict damage on people at the market.

The Chinese government called the early morning attack in Urumqi, the capital of the Xinjiang region, a "serious violent terrorist incident of a particularly vile nature," according to The Associated Press. Previous violent attacks have been blamed on the area's Muslim Uighur minority.

The attackers struck a street market where vendors had set up tables to sell vegetables, eggs and other wares on a tree-lined street. From Shanghai, NPR's Frank Langfitt reports for our Newscast unit:

"Two off-road vehicles drove in opposite directions through a morning street market a little before 8 a.m. [local time] hitting pedestrians, according to Chinese media. The occupants tossed out explosive devices before they came to a stop, and the vehicles exploded."Photos posted to Chinese social media showed the bodies of four people lying in the road who appeared to have been hit. An elderly woman sat next to them, dazed with blood streaming from her forehead."No groups have taken responsibility for the attack, which left more than 90 injured."On April 30, a bombing at the Urumqi train station killed one civilian. A militant group called the Turkistan Islamic Party claimed it was behind the bombing."

Frank also discussed the violence on Morning Edition and noted, "We've never seen a succession of attacks like this."

A man who said he witnessed the scene at the market shortly after the attack described it to Reuters:

"The air was full of the smell of gunpowder and the sound of sobbing," he said. "There were simply too many [casualties], old folks who were at the morning market."

Copyright 2016 NPR. To see more, visit http://www.npr.org/.