Media playback is unsupported on your device Media caption Thomas Martienssen: "The whole mountain just came to life"

The BBC's Thomas Martienssen witnessed the avalanches that killed 18 people on Mount Everest after a massive earthquake in Nepal.

The team had arrived at Camp 1 when the 7.8-magnitude earthquake shook the mountain.

It triggered a wall of snow, rock and ice that hurtled down onto the Everest Base Camp.

More than 5,000 people are known to have been killed and at least 10,000 injured in the earthquake. The Nepalese government estimates that more than a quarter of the population - about eight million people - has been affected.

Here's how @martienssen recorded his experiences of the worst disaster in the history of the world's highest peak.

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Media playback is unsupported on your device Media caption Mountaineer Jost Kobusch filmed the moment of the Mount Everest avalanche

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