A mysterious sinkhole spewing fire and incredible heat has appeared in a hillside on the outskirts of Urumqi, in Xinjiang Uyghur Autonomous Region in north-western China.
Geologists and media have flocked to the desolate mountain since it appeared a few weeks ago. The heat blasting from the 'ring of fire' has been measured at 792C (1457F) from two metres away and is so intense that experts can't get close enough to determine how deep the hole is.
Locals told Chinese media that they had noticed the ground in the area had been warm underfoot for some time. The hill is not in a volcanic area, and experts from local geological bureau think the hole is caused by the layer of spontaneously combusted coal underneath the ground, which leads the surface layer to collapse.
According to the area residents, the phenomenon has existed in the area for a few decades. And smoke often comes from under the ground on this hill in the spring and autumn. Chen Long, a supervisor from Xinjiang Meitian Fire Engineering Bureau, said:
"Primitive mining and extinguishing techniques caused coal to burn deep under the ground. Operators didn’t seal the mines properly after business discontinued and this leads the underground fire to burn towards the surface of the earth." The local authorities have already started drawing plans to put out the underground fire.