A major earthquake has struck eastern Nepal, near Mount Everest, two weeks after more than 8,000 died in a devastating quake.
At least four people have been killed and an unknown number injured, according to aid agencies.
The latest earthquake hit near the town of Namche Bazaar, near Mount Everest.
The US Geological Survey said it had a magnitude of 7.3. An earthquake on 25 April, centred in western Nepal, had a magnitude of 7.8.
The latest tremor was felt in northern India and Bangladesh.
In the Nepalese capital Kathmandu, which was badly damaged last month, people rushed out of buildings as the quake struck at 12:35 local time (07:50 GMT).
The BBC’s Yogita Limaye, who was in Nepal’s mountains when the latest earthquake struck, tweeted: “We’re safe. Did feel the earth shake for quite a long time. Saw dust and stones flying off mountain near by.”
She told BBC World News: “The earth shook and it shook for a pretty long time.
“I can completely understand the sense of panic. We have been seeing tremors: it’s been two and a half weeks since the first quake.
“But this one really felt like it went on for a really long time. People have been terrified.”
At least four people were killed in the town of Chautara, east of the capital, Kathmandu, where a number of buildings are reported to have collapsed.
The International Organisation for Migration said bodies were being pulled from rubble there.
People rushed from buildings in Kathmandu as the quake struck at 12:35 local time (07:50 GMT).
The epicentre of the latest earthquake was 83km (52 miles) east of Kathmandu, in a rural area close to the Chinese border.
It struck at a depth of 18.5km (11.5 miles), according to the US Geological Survey.
The 25 April quake was 15km (9.3 miles) deep. Shallower earthquakes are more likely to cause more damage at the surface.
At the scene: Simon Cox, BBC reporter, Kathmandu
You could feel it really strongly. You could feel it went on for about 25 seconds – the ground was shaking, the birds started squawking, you could feel the buildings shaking.
There was another aftershock and people were all out on the street. That aftershock really added anxiety and panic. People started crying.
They are calm but you can tell they are all scared.
Tuesday’s earthquake is likely to be one of the largest to hit Nepal, which has suffered hundreds of aftershocks since 25 April.
The UN Office for the Co-ordination of Humanitarian Affairs warned that buildings had collapsed in Nepal.
The 7.3 quake was followed 30 minutes later by another large aftershock, centred on the district of Ramechhap, east of Kathmandu, that had a magnitude of 6.3.
Analysis – Jonathan Amos, Science Correspondent
By any stretch, a magnitude-7.3 quake is a big one. It’s not quite as big as 25 April (7.8), which was 5.5 times more energetic – but a major tremor nonetheless.
Since 25 April, the immediate analysis had suggested more activity on the fault was certainly possible because the previous event had not ruptured all the way to the surface.
That meant some of the strain built up in the rocks over the years had not all been released. One has to hope that those buildings that were left damaged and precarious the last time have since been felled in subsequent aftershocks, or have been put out of bounds.
This will limit the casualties this time. But further landslides and avalanches in the mountainous terrain are a persistent risk. And, of course, another big tremor does nothing for the frayed nerves of an already anxious population.