Updated at 12:15 a.m. ET Thursday:

A day after reports surfaced from Mount Everest that four climbers had been found dead, Nepalese officials are casting doubt on the grim news.

Officials with the country's Tourism Department and the Nepal Mountaineering Association say other climbers would have seen the bodies and that no group of four has been reported missing.

Nepalese Sherpas reportedly discovered the bodies in tents at Camp IV, the camp closest to the summit of the world's tallest mountain.

As we reported Wednesday, Mingma Sherpa of the Seven Summits Trek group, the company the Sherpas worked for, told The Associated Press and Reuters that his team had found the four bodies. But he has now cast doubt on when exactly the people might have died — it's not unusual for bodies to remain on the mountain due to the difficulties of finding and recovering them.

The Himalayan Times had reported that two were Nepalese and two were foreigners. It said one was a woman.

If the reports are true, it would bring the death toll for this climbing season to 10.

Ang Tshering of the Nepal Mountaineering Association said that if four people had gone missing, their team members at base camp would have raised an alarm, according to the AP.

And Tourism Department official Durga Dutta Dhakal told the AP on Thursday that 30 other climbers would have passed the place where the bodies were supposedly found, and that none had reported seeing them.

Confusingly, Dhakal also told Reuters: "I can categorically confirm that these bodies are not of the climbers from the current session."

The wire service notes that "the conflicting information has renewed calls for better tracking of people on the mountain as well as screening of climbers and their guides to ensure that only people with experience attempt the 8,850 metre (29,035 feet) summit."

The Times said the Sherpas found the four climbers while trying to recover the body of "49-year-old Slovakian solo climber Vladimir Strba who died at Camp IV on Sunday afternoon."

Everest is particularly busy at the moment because the Nepalese government has issued a record 371 permits for foreign climbers, the AP notes.

Deaths on Everest are tragically common — at least 200 people have been killed attempting to climb it since 1920, the BBC reported. "However, the numbers of people attempting the climb have also skyrocketed since 1990, when the Nepalese government withdrew restrictions on how many teams were allowed on to the mountain — which means the percentage of climbers who die has actually dropped."

British Everest expedition leader Tim Mosedale wrote in a recent Facebook post that the increasing number of climbers has led to more guides who are less-experienced:

"Over the years there's been a huge dilution in the cumulative experience of staff whilst at the same time there's been a net increase in inexperienced or poor expedition providers. When you combine this with a decline in the amount of experience of the clients who are accepted on board it's a worrying equation."

Major causes of death on Everest include "exhaustion, exposure, frostbite, falls and altitude sickness," Reuters reported. "But the biggest killer in recent years has been avalanches."

Avalanches in 2014 and 2015 meant that many people who intended to climb the mountain had to delay their attempt, the AP reported, which may have contributed to the higher number of climbers this year.

Five others have died this season: Ravi Kuma of India, Roland Yearwood of Alabama, Francesco Enrico Marchetti of Australia, Min Bahahur Sherchan of Nepal and Ueli Steck of Switzerland.

Despite the bleak news, there's also been some inspiring developments on Everest this season. The BBC reports two new possible speed records:

"[A] 29-year-old Spaniard is being hailed as having reached the summit in the fastest-ever time, without rope or extra oxygen.

"Kilian Jornet reached the top, from the Tibetan side, in just 26 hours, his team said yesterday. The record cannot be verified until he returns.

"An Indian woman, Anshu Jamsenpa, is also believed to have set the new woman's record for the fastest double ascent, having climbed the mountain twice in one week."

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