Hundreds of people injured in the 7.1-magnitude earthquake that hit northwest China's Qinghai Province early on Wednesday are being transported to large cities out of the quake zone for treatment.

Twenty four injured arrived at an airport of Lanzhou City, capital of northwest China's Gansu Province, at 6:10 p.m. Thursday by a military plane, said Li Yulin, a spokesman with Qinghai's public health department.

They were accompanied by many of their family members. Upon landing, the injured and their families were immediately taken to four large hospitals in Lanzhou by ambulances, Li said.

Another 38 injured arrived at airport of Xining City, Qinghai's capital at 2:50 p.m., from where they were transported to local hospitals, he added.

At 5:06 p.m., a plane carrying 36 injured landed at an airport in Chengdu City, capital of Sichuan Province. They are now being looked after at two of the city's best hospitals.

A total of 550 injured are scheduled to be transported from the quake zone either by air or on land on Thursday. Of them, 350 will be treated in Xining, he said.

The quake has devastated most of the medical facilities in the quake zone which is in urgent need of medical workers and equipment.