An explosion occured in Urumqi, the capital of northwest China’s Xinjiang region, the official Xinhua news agency tweeted. Xinhua said it wasn't known whether there were casualties, but that at least four bodies were spotted. Horrific photos began to flood the Internet as many sent their virtual condolences to the families of victims. Reuters reported that the blast took place at a street market and that it was caused by colliding vehicles.

Flames and heavy smoke were observed after the blast, which reportedly took place at about 8 a.m. local time, Xinhua noted, as reported by Reuters. Xinjiang isn’t a stranger to violence. There have been a number of bomb and knife attacks in the region over the past few months, which China blames on separatist militants. 

Though there is no official word on the amount of injuries, some users on Twitter began to comment as many as seven dead bodies were seen.