Helicopters were deployed on Monday to rescue climbers still stranded high on Mount Everest after an earthquake-triggered avalanche killed at least 18 people on the world's highest peak, officials said.

Three helicopters were sent for about 150 climbers trapped at Camps One and Two after Saturday's avalanche sent down slabs of ice and snow, cutting them off from base camp below, the Nepalese officials said.

The climbers, who were not thought to be seriously injured, were being brought down to base camp rather than all the way down the mountain, tourism department chief Tulsi Gautam told AFP.

"We have deployed three helicopters today to bring climbers down from Camp One and Two. They are safe but we need to bring them down because part of the route is damaged," Gautam said.

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He said the climbing season might again be called off in the wake of the avalanche that swept through base camp, triggered by the massive quake that devastated parts of Nepal.

"It is possible that climbing might not continue this year. However, there has been no official decision," he said.

[PHOTO GALLERIES]:
Nepal earthquake
Mount Everest Avalanche

Helicopters have already rescued scores of climbers and their teams injured at base camp in Saturday's avalanche, which sent a cloud of snow cascading down the mountain.

There had been more than 800 people at different places on the mountain, which has also felt a series of aftershocks, an official has said.

Many had travelled to Nepal for the start of the annual climbing season, which was cancelled last year after 16 sherpa guides were killed in what was previously the deadliest disaster in the mountain's history.
“
Only 2 people per shuttle due to high altitude
”
- Climber, Alex Gavan
Romanian climber Alex Gavan reported Monday the evacuation efforts on social media.

"Stranded climbers evacuation from camp1&2 continues. 3 helis fly non-stop. Only 2 people per shuttle due to high altitude. Weather good."

Another tourism official, Gyanendra Kumar Shrestha, estimated some 150 people were stranded at or between Camps One and Two.

Pictures taken by AFP's South Asia photo chief Roberto Schmidt showed an enormous cloud of snow and debris cascading down the mountain on Saturday, while survivors have told of the horrifying moment when the disaster struck.