Videos published by China's state broadcaster CCTV showed houses destroyed with walls torn apart.

Rescue workers waded through rubble strewn across the ruins in the aftermath, footage showed, while some gave locals thick blankets to keep warm in subzero temperatures.

The quake struck rural, high-altitude Tingri county, about 80 kilometres (50 miles) north of Mount Everest near China's border with Nepal, at around 9:00 am Tuesday.

Sangji Dangzhi, whose supermarket in Tingri suffered considerable damage, described the situation as "very serious", with ambulances taking people to hospital throughout the day.

"Here the houses are made from dirt so when the earthquake came... lots of houses collapsed," the 34-year-old told AFP by phone.

Surveillance images published by CCTV showed people running through a store's aisles as shelves shook violently, sending objects like toys tumbling to the ground.

Some 95 people have been confirmed dead and 130 others injured as of 3:00 pm (0700 GMT), Xinhua news agency said.

More than a thousand houses have been damaged, it reported earlier.

The China Earthquake Networks Center (CENC) measured the quake's magnitude as 6.8, while the US Geological Survey reported it as 7.1.

When tourist Meng Lingkang arrived in the town of Lhatse, 65 kilometres from the epicentre, where he had booked a restaurant, "the buildings had cracked open".

"Some of the older houses collapsed, and a large part of the buildings made from bricks had cracked open, with big fissures," the 23-year-old told AFP.

Videos geolocated by AFP to Lhatse showed debris scattered in front of streetside eateries.

"There were quite a few (rescue vehicles). One after the other they arrived," Meng added.

- 'All-out rescue efforts' -

The area most affected is surrounded by mountainous terrain on the Chinese side of Mount Everest.

Tingri, the epicentre, is home to around 62,000 people, and is much less developed than urban centres like Tibet's capital Lhasa.

Many of the fallen houses appeared to be constructed using traditional materials such as stone, mud bricks and wooden beams.

Chinese President Xi Jinping has called for "all-out search and rescue efforts, minimising casualties to the greatest extent possible, properly resettling affected residents, and ensuring their safety and warmth through the winter", CCTV said.

Temperatures in Tingri are projected to drop to minus 16 degrees Celsius (3.2 Fahrenheit) overnight, according to the China Meteorological Administration.

Authorities said over 3,400 rescuers and more than 340 medical workers had been deployed.

Aid including cotton tents, quilts and cold-weather equipment had been dispatched by central authorities, Xinhua said.

Tingri is under the administration of the prefecture-level city of Shigatse, home to the traditional seat of the Panchen Lama, one of the most important spiritual figures in Tibetan Buddhism after the Dalai Lama.

The Dalai Lama said he was "deeply saddened".

"I offer my prayers for those who have lost their lives and extend my wishes for a swift recovery to all who have been injured," the exiled spiritual leader said in a statement.

Russian President Vladimir Putin expressed his "sincerest condolences", saying Russia "shares the grief of those who have lost relatives and close ones".

- 'Shook quite strongly' -

As well as Kathmandu, areas around Lobuche -- in the high mountains near Everest in Nepal -- were also rattled by the tremor and aftershocks.

"It shook quite strongly here, everyone is awake," said government official Jagat Prasad Bhusal in Namche region, which lies closer to Everest.

Security forces had been deployed but no damage or deaths had been reported so far, Nepali home ministry spokesman Rishi Ram Tiwari said.

Nepal lies on a major geological faultline where the Indian tectonic plate pushes up into the Eurasian plate, forming the Himalayas, and earthquakes are a regular occurrence.

In 2015, nearly 9,000 people died and more than 22,000 were injured when a 7.8-magnitude quake struck Nepal, destroying more than half a million homes.

Some tremors were felt in Bihar state in India but no injuries were reported.

Tuesday's quake was the most powerful recorded within a 200-kilometre (124-mile) radius in the last five years, the CENC said.

A quake in December 2023 in northwest China killed 148 people and displaced thousands in Gansu province.

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