Survivors of China's deadliest earthquake in years huddled in makeshift aid tents despite freezing temperatures on Wednesday, too scared to return to homes made dangerous by the disaster.

State broadcaster CCTV said at least 134 people were killed in northwestern Gansu province and neighbouring Qinghai after a shallow tremor on Monday night damaged thousands of buildings.

Almost 1,000 were injured across the two provinces, according to state news agency Xinhua, while CCTV said 13 were still missing in Qinghai as of 4:00 pm (0800 GMT) Wednesday.

The quake was China's deadliest since 2014, when more than 600 people were killed in southwestern Yunnan province.

AFP reporters saw families sheltering in makeshift tents built from wooden poles and tarpaulins outside the Majiahe mosque near the epicentre in Gansu's Jishishan county, with outdoor stoves and blankets salvaged from homes their only sources of warmth.

A woman taking refuge in one of the tents outside the mosque told AFP her family was afraid to return home.

"We can't get inside anymore, it's too dangerous," she said, declining to give her name. "All the bricks and tiles inside could fall down at any time."

Residents crowded around stoves in large tents set up on a basketball court by the local government in a nearby township.

One resident told AFP some tents had as many as 35 people huddled inside them.

"We have eight people in our family but (emergency response staff) only gave us three servings of instant noodles last night," local student Ma told AFP.

"There is nothing we can do. We can't go back to our house now," she said.

Children lay under blankets, playing on their phones, while adults attempted to prepare meals from the limited food rations.

AFP saw rescue teams unloading large bundles of supplies, including more tents.

In another nearby town, people were seen queuing up for food and supplies beneath a large mosque, its roof panels almost entirely knocked down by the tremor.

Next to the damaged mosque were more than 150 blue emergency tents, each allocated to one family, an official at the scene told AFP.

Dozens of aftershocks

Nearly a thousand people who were injured have been sent to hospitals, with 87,000 people moved to "temporary shelters" in Gansu alone, CCTV said.

China's western hinterland carries the scars of frequent seismic activity. A huge quake in Sichuan province in 2008 left more than 87,000 people dead or missing, including 5,335 schoolchildren.

"Search and rescue work basically ended by 3:00 pm yesterday and the main work now is to treat the injured and resettle the affected population," an unidentified official from Gansu's Emergency Management Department told a news conference on Wednesday.

The US Geological Survey said Monday night's magnitude-5.9 quake struck at a shallow depth at 11:59 pm local time (1559 GMT) with its epicentre around 100 kilometres (60 miles) from Gansu's provincial capital, Lanzhou.

Dozens of smaller aftershocks followed and officials warned that tremors with a magnitude of more than 5.0 were possible in the next few days.

Fears are growing that survivors could succumb to the bitter cold, with temperatures in Jishishan expected to dip as low as -17 degrees Celsius (1.4 Fahrenheit) on Wednesday.

Thousands of firefighters and rescue personnel have been sent to the disaster zone and state media said 2,500 tents, 20,000 coats and 5,000 rollaway beds had been sent to Gansu.