A Nepalese mountaineer is disputing the time set for the fastest Mount Everest ascent that broke his own record.
By Navin Khadka
BBC reporter in Kathmandu
Pemba Dorjie Sherpa says his rival did not climb the mountain in the officially accepted time of 10 hours and 56 minutes, and wants an inquiry.
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The record holder, Lakba Gelu Sherpa, has denied foul play and says he has all the proof he needs of his achievement.
The climbs took place last month during the golden jubilee of the first Everest ascent.
Other records set for the anniversary included the oldest and youngest people to make it to the top, and the first black climber on the summit.
The drama between the two Sherpas began on 23 May when Pemba Dorje recorded a time of 12 hours and 45 minutes to the summit, knocking nearly four hours off the previous record.
I have those photographs with me now and I can produce them whenever wanted
Just three days later, the Nepal Government announced that Lakba Gelu had reached the summit in less than 11 hours.
Pemba Dorje, 22, says some climbers have reported meeting Lakba Gelu still climbing uphill, several hours after he is recorded as reaching the peak.
Pemba Dorje says his rival was several hundred metres from the top at the time.
He also says Lakba Gelu has no photographic evidence of having climbed Mount Everest.
Lakba Gelu says he has photographs and his achievement was witnessed by Appa Sherpa who - after climbing Everest 13 times - holds a record for the greatest number of ascents.
"Appa Sherpa is the eyewitness who saw me reaching the top at around four in the morning. He used my radio set to inform the base camp that I had climbed the mountain in a record time," Lakba Gelu told the BBC.
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"Appa signed the flag I was carrying and he also took my photographs on the summit. I have those photographs with me now and I can produce them whenever wanted."
Lakba Gelu said if an investigation took place, it was likely only to increase his popularity as the record holder.
Nepal's Tourism Ministry says it will speak to both men before any decision on the controversy is made.