KATMANDU, Nepal (KCBS/AP) – The world’s highest mountain saw its deadliest-ever disaster Friday.

As Nepalese Sherpa guides worked to set up ropes for other climbers on Mount Everest, an avalanche swept down the climbing route. At least 12 of the guides were killed, and four others are missing. Several more were hurt.

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KCBS has obtained photos from an American who was on the mountain when the avalanche happened. He took photos of the aftermath not far from where he was camped with his iPhone.

Avalanche on Mt Everest

Aftermath on avalanche at Mt Everest. Photo courtesy of Roger Philipp

Avalanche on Mt Everest

Aftermath of avalanche on Mt Everest. Photo courtesy of Roger Philipp

He said he was writing as they were bringing the bodies down. He is doing fine and has agreed to an interview as soon as we can establish contact.

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Meantime, according to Associated Press another injured survivor told relatives that the path up the mountain was unstable just before the avalanche.

Hundreds of climbers, guides and support crews were at Everest’s base camp when the avalanche happened. They’ve been preparing to climb to the summit when weather conditions will be at their most favorable early next month. They’ve been setting up camps at higher altitudes, and guides have been fixing routes and ropes on the slopes above.

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