Deadly road accidents are common in China, where traffic regulations are often flouted or go unenforced by police.

At least 36 people were killed and 13 injured when a bus slammed into a tunnel wall on an expressway in northern China, state media said on Friday.

The coach crashed in Shaanxi province on Thursday night after departing from Chengdu in southwest Sichuan province en route to the central city of Luoyang, according to Xinhua news agency, which cited local authorities.

The injured have been rushed to hospital, Xinhua said.

Sichuan province is already reeling from another tragedy as 20 people were killed and hundreds more injured in an earthquake that struck the region on Tuesday night.

Deadly road accidents are common in China, where traffic regulations are often flouted or go unenforced by police.

The country's frequently overcrowded long-distance buses are particularly prone to fatalities.