Nepal earthquake: At least 79 killed from Tuesday's aftershock

Officials with bullhorns walked through the quake-damaged streets of this small Nepal town Wednesday, calling for people to leave the damaged buildings.

The evacuation orders came a day after Nepal, just beginning to rebuild after a devastating April 25 earthquake, was hit by magnitude-7.3 quake. Tuesday's earthquake killed at least 79people, injured nearly 2,300 and caused landslides that blocked roads and slowed the delivery of relief supplies.

"There is danger!" the officials called out over the bullhorns. "Leave the buildings!"

Most people, though, had fled into the open the day before, and had spent the night in tents or under plastic tarps.

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Meanwhile, a U.S. Marine Corps helicopter carrying six Marines and two Nepalese soldiers was reported missing while delivering disaster aid in the country's northeast, U.S. officials said, although there have been no indications the aircraft crashed.

Home ministry official Laxmi Dhakal said Wednesday that army helicopters were scouring the Sunkhani area, nearly 80 kilometres northeast of Kathmandu, for the missing helicopter.

Tuesday's magnitude-7.3 quake, centred between Kathmandu and Mount Everest, struck hardest in the foothills of the Himalayas. Most of the 65 people confirmed dead by Wednesday morning were in Dolakha district, northeast of Kathmandu, said the district's chief administrator, Prem Lal Lamichane.

"People are terrorized. Everyone is scared here. They spent the night out in the open," Lamichane said, adding the administration was running out of relief material.

He asked the government to send more helicopters and supplies, and said there were many injured people stranded in villages.

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Tuesday's quake also left nearly 2,000 injured, according to the Home Ministry's latest count. But that toll was expected to rise as reports trickled in of people in isolated Himalayan towns and villages being buried under rubble, according to the UN's Office for the Coordination of Humanitarian Affairs.

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.

But while Tuesday's quake was terrifying and deadly, it was significantly less powerful than April's and occurred deeper in the Earth. Calculations done by University of Michigan earthquake geophysicist Eric Hetland indicated that about 65,000 people were exposed to "violent" shaking Tuesday compared to 1.5 million on April 25.

The first quake also drove many people from damaged homes, and officials in Kathmandu and other towns reported the collapse Tuesday of empty buildings.

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Impoverished Nepal appealed for billions of dollars in foreign aid after the first quake, 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.

In Washington, Navy Capt. Chris Sims said the missing Huey helicopter was conducting disaster relief operations near the Nepal town of Charikot.

A nearby Indian helicopter heard radio chatter about a possible fuel problem, said U.S. Army Col. Steve Warren. The Huey, carrying tarps and rice, had dropped off supplies and was headed to a second site when contact was lost, he said, adding that there has been no smoke or other signs of a crash.

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Due to the rugged terrain, the helicopter could have landed in an area where the crew was unable to get a beacon or radio signal out, Warren said.

In the capital, frightened residents who had returned to their homes only a few days ago had to again set up tents Tuesday night to sleep in empty fields, parking lots and on sidewalks.

"Everyone was saying the earthquakes are over. ... Now I don't want to believe anyone," said 40-year-old produce vendor Ram Hari Sah.