Mark Inglis, a double-amputee, said David Sharp lacked enough equipment and oxygen to make it down the mountain so there was no use in trying to save him.
Sharp died under a rock nearly 1,000 feet below Everest's summit, the New Zealand Herald reports.
An estimated 40 other climbers passed by Sharp on their way to the top as well.
Joining Inglis' defense is Sharp's mother who told the Herald, "Your responsibility is to save yourself -- not to try and save anybody else."
But Edmund Hillary, who with Tenzing Norgay was the first to climb to the top of Mount Everest, said Inglis and the other climbers should have tried their best to save Sharp, adding "You have a duty, really, to give all you can to get the man down and getting to the summit becomes very secondary."
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