CALGARY - A Calgary mountain climber has died on Mount Everest after making it to the top without the use of oxygen.

At least two climbing websites are confirming the death last week of Frank Ziebarth, 29, who moved to the city two years ago from Germany.

Ziebarth is reported to have reached the summit on the Tibetan side, and was last seen at 8,700 metres determined to descend under his own strength.

One website says he was suffering from hypothermia and obvious lack of oxygen.

It was later confirmed by fellow climbers that his body remains on the mountain.

Ziebarth was an accomplished climber who had already conquered at least three peaks without the use of oxygen.