Nepal, May 22 -- An expert mountain guide successfully put four of his clients on top of Mount Everest on Wednesday less than a week after they left London, one of the fastest ascents on record of the world's highest peak.

The four British climbers flew from London to Kathmandu on May 16 and reached the 8,849-meter (29,032-foot) summit Wednesday morning local time, according to Lukas Furtenbach, who has been using different methods over the past five years to speed up the climb.

The climbers had put in months of preparation, training in hypoxia tents and undergoing xenon gas treatment at a clinic in Germany before heading to Nepal.

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