A new earthquake and powerful aftershocks killed dozens of people and brought fresh terror to a traumatised Nepal on Tuesday as buildings already damaged in a monster quake last month came tumbling down.
Only weeks after the country's deadliest quake in more than 80 years, terrified residents once again fled onto the streets while lawmakers had to scurry from parliament as the earth began shaking beneath their feet.
Officials in Nepal said at least 36 people were killed while 17 people also died across the border in northern India, most in the state of Bihar.
The 7.3-magnitude quake struck at 12:35 pm, some 76 kilometres (47 miles) east of Kathmandu, the US Geological Survey said, after a 7.8-magnitude quake on April 25 killed more than 8,000 people.
Tuesday's quake was felt as far away as New Delhi, and officials said it caused buildings to collapse in Tibet in neighbouring China, killing at least one person there.
A second tremor of 6.3-magnitude struck Nepal around half an hour later, followed by yet more aftershocks, according to the USGS.
Nepalese television showed buildings including parliament swaying as the earth moved underneath, while footage also emerged of fresh landslides in rural areas.
"At an hour of a natural disaster like this, we have to face it with courage and patience," Nepal's Prime Minister Sushil Koirala said after an emergency meeting of his cabinet.
The Nepalese government has acknowledged that it was overwhelmed by the scale of the April 25 disaster which destroyed nearly 300,000 homes and left many more too dangerous to live in any more.
Laxmi Prasad Dhakal, a spokesman for Nepal's home ministry, said 36 people were killed and 1,129 were injured.
- 'Houses have collapsed' -
The districts of Dolakha and Sindhupalchowk, two of the worst affected by the original quake last month, bore the brunt of the damage once more.
"Many houses have collapsed in Dolakha, many houses have collapsed and there is a chance that the number of dead from the district will go up," said Home Minister Bam Dev Gautam.
The Red Cross said it had received reports of large-scale casualties in the town of Chautara in Sindhupalchowk, where its Norwegian branch is running a field hospital.
"Now hundreds of people are pouring in. They are treating dozens for injuries and they have performed more than a dozen surgeries," said Red Cross spokeswoman Nichola Jones.
Patrick Fuller, another Red Cross spokesman, said there also had been reports of landslides in Tatopani, near the Chinese border.
Save the Children said two major buildings had collapsed in Kathmandu's Balaju Nayabazar area while many more multi-storey buildings were showing large fissures.
The Gorkha region had also been hit by landslides and many key roads were blocked, the British charity added.
Residents of Kathmandu meanwhile described their sense of terror when the quake struck.
"We felt it and suddenly there were huge crowds running up and down," said Suresh Sharma, who was in a vegetable market at the time.
"It was very scary and very difficult to make my way out," said 63-year-old.
"The last time we had the big quake I ran out of my house and barely escaped. This one felt just like that one. I can't believe it's happening again."
- 'A boat on rough seas' -
Rose Foley, working in Kathmandu for the UN's children's fund UNICEF, said staff dived under tables as the ground swayed for around a minute.
"The shaking seemed to go on and on. We got out to safety as soon as possible. Sitting out in the open it felt like I was on a boat on rough seas as aftershocks hit," she said by email.
Although the latest quake did not appear to be as severe as the April 25 one, residents were terrified that buildings that were already badly damaged could come crashing down.
"I was thinking of moving to a rented room, but today was so scary I can't risk my family's life," Dipak Koirala, who has been living under a tent since April 25, said by phone from central Ramechhap district.
"We will continue to stay in the tent but it's wet here and the rain came into the tent, which we are sharing with 24 people."
Kathmandu's Tribhuvan International Airport, the main entry point for flights bringing in aid, was briefly closed again Tuesday as a precaution.
Relief teams from around the world are still working to provide water, food and medical assistance to Nepalis after the April 25 quake.