Another earthquake killed dozens of people Tuesday and spread more fear and misery in Nepal, which is still struggling to recover from a devastating quake nearly three weeks ago that left more than 8,000 dead.

A U.S. Marine Corps helicopter carrying six marines and two Nepalese soldiers was reported missing while delivering disaster aid in northeastern Nepal, U.S. officials said, although there have been no indications the aircraft crashed.

The magnitude 7.3 quake, centred midway between Kathmandu and Mount Everest, struck hardest in the foothills of the Himalayas, triggering some landslides, but it also shook the capital badly, sending thousands of terrified people into the streets.

Nepal's parliament was in session when the quake hit, and frightened lawmakers ran for the exits as the building shook and the lights flickered.

At least 37 people were killed in the quake and more than 1,100 were injured, according to the Home Ministry. But that toll was expected to rise as reports began reaching Kathmandu of people in isolated Himalayan towns and villages being buried under rubble, according to the UN's Office for the Co-ordination of Humanitarian Affairs.

Dozens more die in a quake, as Nepal struggles to recover from a devastating quake nearly three weeks ago that left more than 8,000 dead 4:41

Tremors radiated across parts of Asia. In neighbouring India, at least 16 people were confirmed dead after rooftops or walls collapsed onto them, according to India's Home Ministry. Chinese media reported one death in Tibet.

The earthquake that hit April 25 killed more than 8,150 and flattened entire villages, leaving hundreds of thousands homeless.

At least three people were rescued Tuesday in Kathmandu, while another nine were pulled to safety in the district of Dolkha, the government said.

Dr. Dybesh Regmi, who travelled back to his native Nepal from Canada to help, told CBC News when the quake hit he was in a medical camp in Bhaktapur.



"The ground just completely started shaking, enough that I couldn't stand up on my two feet," said Regmi, who arrived in Nepal two days ago.

Children in the tents stated screaming and crying, he said.

"Their parents started running around looking for their kids … it was just chaos."

Search parties fanned out to look for survivors in the wreckage of collapsed buildings in Sindhupalchowk's town of Chautara, which had become a hub for humanitarian aid after last month's magnitude 7.8 earthquake, the country's worst-recorded quake since 1934.

Kathmandu residents gather under an awning as they prepare to spend the night out in the open after another earthquake strikes the Himalayan nation. (Roberto Schmidt/AFP/Getty Images)

CBC's Adrienne Arsenault, who recently returned from covering the aftermath of the devastating April 25 quake in Nepal, said there were no injuries among members of Canada's Disaster Assistance Response Team after the latest quake. The team is helping provide aid in Nepal.

Lt.-Cmdr. Kelly Williamson of DART said one of its teams was physically cut off and heavy equipment had to be sent to clear a road to them.

Williamson said DART will be heading into the countryside on Wednesday to assess damage.

The Canadian Red Cross, which has a team of 17 in Dhunche and a team of nine in Khukondole, said all of its members are safe.

Canadian Emilie-Anne Leroux, who is in Nepal working for the UN Office for the Co-ordination of Humanitarian Affairs, was next to a Norwegian Red Cross field hospital in the hard-hit area of Chautara when the latest earthquake hit.

"We were seeing powder rising, dust, debris rising from the village down the road," she told CBC News.

Impoverished Nepal appealed for billions of dollars in aid from foreign nations, as well as medical experts to treat the wounded and helicopters to ferry food and temporary shelters to hundreds of thousands left homeless amid unseasonal rains.

Tuesday's quake was deeper, however, coming from a depth of 18.5 kilometres versus the earlier one at 15 kilometres. Shallow earthquakes tend to cause more damage.

Nepalese military personnel remove debris in search of survivors after a fresh magnitude-7.3 earthquake struck Kathmandu on Tuesday. (Athit Perawongmetha/Reuters)

Tuesday's quake was followed closely by at least 10 strong aftershocks, according to the U.S. Geological Survey.

Early reports indicated at least two buildings had collapsed in Kathmandu, though at least one had been unoccupied due to damage it sustained on April 25. Experts say the earlier quake caused extensive structural damage even in buildings that did not topple, and that many could be in danger of collapse.

"Everyone was saying the earthquakes are over.... Now I don't want to believe anyone," said 40-year-old produce vendor Ram Hari Sah as he searched for a spot to pitch an orange tarpaulin to shelter his family. "We are all scared, we are terrified. I would rather deal with mosquitoes and the rain than sleep in the house."

Extra police were sent to patrol ad-hoc camping areas, while drinking water and extra tents were being provided, according to Kathmandu administrator Ek Narayan Aryal.

"I thought I was going to die this time," said Sulav Singh, who rushed with his daughter into a street in the suburban neighbourhood of Thapathali. "Things were just getting back to normal, and we get this one."

Paul Dillon, a spokesman with the International Organization for Migration, said he saw a man in Kathmandu who had apparently run from the shower with shampoo covering his head. "He was sitting on the ground, crying," Dillon said.

The earth also shook strongly across the border in Tibet, unleashing a landslide that killed one person and injured three, according to China Central Television. Two houses also collapsed, the state broadcaster said, quoting disaster relief headquarters of the regional Tibetan government.