XI'AN -- At least 36 people were killed and 13 others injured in an expressway accident in northwest China's Shaanxi Province Thursday night, authorities said Friday morning.

The accident occurred at 11:34 p.m. in Ankang City when a coach carrying 49 people hit the wall at the mouth of the No. 1 Qinling tunnel on the Xi'an-Hanzhong section of the Beijing-Kunming Expressway, according to the State Administration of Work Safety.

The coach was en route to Luoyang City, central China's Henan Province, from Chengdu City, capital of southwest China's Sichuan Province.

Operated by Luoyang Transportation Group Co., Ltd, the coach has a designed carrying capacity of 51 people.

The injured have been rushed to the hospital.

One picture sent from the site to Xinhua showed rescuers were examining the smashed front part of the vehicle while another gave a view of the tunnel mouth with a yellow sign warning of possible accidents and requiring careful driving.

The State Administration of Work Safety and the Ministry of Public Security have dispatched work teams respectively to oversee investigation and handling of the aftermath.