A magnitude 6.7 aftershock has rocked the already earthquake ravaged Nepal, sending residents of Kathmandu running for safety and triggering even more avalanches on Mount Everest.  This latest aftershock struck north east of Kathmandu near the Nepal border with China at a depth of 10 kilometers, according to the United States Geological Survey (USGS).

Climber Jim Davidson said he felt the aftershock at Camp 1 on Mount Everest.  "Just had our biggest aftershock yet here at C1 on Everest. Smaller than original quake but glacier shook & avalanches," he tweeted. Another climber at the Makalu base camp near Everest said, "Another one, we have an aftershock right now.  Oh shit!  "Avalanche!", he shouted.

The subsequent avalanches occurred just after helicopters airlifted those that were injured after the first quake rocked the area on Saturday, when a wall of snow hit the base camp, killing at least 18 people. This marks the deadliest disaster for Everest and comes exactly a year after an avalanche killed 16 sherpa guides, forcing the season to be cancelled. The strong aftershock shut down Nepal's International Airport briefly, forcing some planes to turn around midflight.  It shook buildings as far away as the Indian capital New Delhi, halting the city metro.

"There is no way one can forecast the intensity of aftershocks so people need to be alert for the next few days," said LS Rathore, chief of India's state-run weather office.

Remote areas in the region also felt the rumblings of the ground.  Tanya Barron of the charity Plan International UK said she saw the buildings shake and vehicles move across the road.

"We've been travelling through remote villages and areas. We were moving along today and the road was shaking. We could see the buildings shaking, big four-wheel drive vehicles moving across the road," she said.

The local hospitals have been overstretched, where medics were having treating patients in hastily erected tents.

"Electricity has been cut off, communication systems are congested and hospital are crowded and are running out of room for storing dead bodies," Oxfam Australia chief executive Helen Szoke said.

As rescuers combed through the huge piles of debris and rubble searching for survivors, the hospitals quickly became overwhelmed with victims who suffered multiple fractures and trauma.

"We have treated many people since yesterday, the majority children," Samir Acharya, a doctor at Nepal's Annapurna Neurological Hospital, says. "Most patients have head injuries or fractures. Two of our patients died, two are critical."

The first quake, measuring magnitude 7.9, hit near Kathmandu around lunchtime on Saturday, sending many building crashing to the ground and triggering the deadly avalanche on Mount Everest. So far, more than 2,500 people have been killed and 6,000 others injured by the quake in the country's worst disaster in 80 years,

"We have deployed all our resources for search and rescues," national police spokesman Kamal Singh Bam says. "Helicopters have been sent to remote areas. We are sifting through the rubble where buildings have collapsed to see if we can find anyone."