A major earthquake has struck eastern Nepal, the second one in two weeks.
The US Geological Survey says Tuesday's quake has a magnitude of 7.3.
At least 29 people have been killed and 1,006 injured in Nepal, officials say.
More than 8,000 people were killed in the first, devastating quake on 25 April.
Abinash, Biratnagar, Nepal: DUCK, COVER AND HOLD. I am an engineer by profession & shared the ways to be safe from earthquake with many fellows but at the moment when earthquake is felt, the panic created within everyone makes their mind nil. Nearby, I saw everyone running haphazardly shouting & crying on the way to my home.
tweets, external: Dr Lalit was in air with MSF heli above Namche (#EarthquakeAgain) trying to land; saw houses broken, landslides: lots of landslides..
Image source, Saurav RegmiSaurav Regmi took this photo in Basundhara, Kathmandu, and says: "Hospital workers were shifting patients to roadside temporary tents. After the Tuesday quake, it is not safe for anyone to stay inside the already cracked buildings."
Dev, Delhi, India: The aftershocks of the earthquake felt today at New Delhi were quite horrendous as people ran out of their high-rise buildings towards open spaces - though the potential damage caused by this current earthquake in New Delhi or parts of northern India were quite negligible. However, I feel grief-stricken thinking about the crisis that has fallen upon the innocent children and people of Nepal.
Geeta Pandey
BBC News, Delhi
The Nepalese government tells the BBC the number of dead has risen to 29, with 1,006 injured. It says 31 of the 75 districts are affected.
Image source, Richard JonesBritish tourists Richard Jones and his friend, James Watson, were on the way to the immigration office in Kathmandu when the latest quake hit. "The taxi driver didn't have control of the steering as if he was being forced down a slalom course. We shouted at him to stop in an area that was safe. Getting out it felt like we were on a swaying boat. Roads were jammed and the local drivers behaving erratically. We ended up walking back across the city."
tweets:, external Interior Ministry says more than a dozen people are already dead in #Nepal #EarthquakeAgain. Several landslides triggered due to the quake.
Sandesh Shrestha, Kathmandu, Nepal: And just when we thought the worst part was over, Mother Earth sought to crush our hopes. At first we thought it was another normal aftershock, but then it started shaking harder. Within seconds everyone was across the streets, away from the taller buildings. The water inside the "dhungedhara" (stone water tap) was shaking violently as well and the top of an old building, already cracked, went down. It seems we'll be spending another three nights under the open sky.
Former Nepal correspondent Charles Haviland said the earthquake will have caused "psychological damage".
"That sense of returning normality with aid being delivered to villages and people finding reasons for a bit of optimism, a bit of cheer in their lives, suddenly that sense of security I think will be knocked quite badly."
Shalav in Bouddha, Kathmandu: This was a real big one and I was having lunch with my co-workers when we all ran. It was the screaming of the people and the noise of the earth, building and windows shaking that frightened me the most. No casualties near my place though, I just hope the rest of my country is like that.
Image source, United World SchoolsThe United World Schools team messaged us on WhatsApp; they are currently searching for people trapped in collapsed buildings (like the one above) in the community of Baga, around 20km (12.5 miles) from the epicentre.
Roshan Kumar, Kathmandu, Nepal: It feels more new quakes are coming to us rather than only aftershocks. People are already terrified and this adds to more anxiety and fear. The buildings that'd cracked and loosened earlier are bound to fall and [I] have heard many houses have collapsed...
Image source, ReutersKent Page from Unicef tells the BBC he was in a school in Kathmandu assessing damage when the quake hit. He said: "We thought the school was going to collapse. People were very, very scared. It was scary for me. I can't imagine what it's like for children who have now been through two earthquakes. We are very concerned about the children of Nepal."
The quake was felt very strongly in the Tibetan town of Zhangmu near the border with Nepal, Chinese state news agency Xinhua reports.
A police rescuer in the town told reporters he saw rocks rolling down the mountains, blocking roads. He also saw large landslides on the Nepalese side. So far there have been no reports of casualties in Tibet.
Nepal's Information Minister Minendra Rijal tells the BBC that 16 people have died and 846 people have been injured in Tuesday's earthquake.
Image source, Kashish Das Shrestha@kashishds tweets:, external This building collapsed in Naya Bus Park today's quake; Nepali security forces working to rescue elderly woman inside
Image source, Anukram AdhikaryAnukram Adhikary messaged the BBC to say: "The earth shook for what felt like eternity. All of my family and the neighbours are now all crammed up in our backyard, making fire to fend off mosquitoes."
tweets, external: For #NepalEarthquake news today, follow @svbel, @kashishds, @kundadixit, @salokya who are on the streets and tweeting great information.
At least 14 people have died in Nepal's latest quake - including five in Sindhupalchowk, the district to the east of Kathmandu that reported the most deaths in the 25 April earthquake, Nepalese officials say.
In neighbouring India, at least five people have been killed, Reuters news agency reports.
Jackson Subedi is an aid worker in Baluwatar, Kathmandu, Nepal: "We are safe but the earthquake this time was also dangerous. We could just run outside our house. I saw a nearby wall collapse and it injured one relative of ours. We don't know if this is an aftershock or another devastating quake."