The avalanche that rolled across Everest base camp came through with the force of a tornado, according to American scientist Jon Kedrowski. Kedrowski was at the camp when an earthquake struck Nepal on Saturday, triggering the slide of snow that killed at least 18 people on the mountain, including four Americans.
Kedrowski says the people who were killed were either in their tent or walking around base camp at the time of the avalanche.
"It was such a powerful force that it knocked people off their feet, it blew people across the glacier for several hundred yards, "said Kedrowski.
Kedrowski explained to CBS News that this wasn't the typical avalanche where snow cascades and buries everyone. Instead, Kedrowski says, the incredible force of air created by the avalanche was responsible for most of the destruction and deaths.
Watch the video above to hear Kedrowksi describe the moment of impact.