A Dutch man and an Australian woman died of apparent altitude sickness while descending from the summit of Mount Everest in the first deaths this year on the world's highest mountain.

Eric Arnold, 35, had enough bottled oxygen with him, as well as climbing partners, but he complained of getting weak and died on Friday night near South Col before he was able to get to a lower altitude, said Pasang Phurba of the Seven Summit Treks agency in Kathmandu, Nepal.

Just hours after Arnold died, Australian climber Maria Strydom also showed signs of altitude sickness on Saturday afternoon before she died, Phurba said.

Both climbers that died were part of the same expedition team. It was still undecided when and if their bodies would be brought down from the high altitude and it would depend on the team and family members, he said.

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Strydom was a finance lecturer at Monash University's business school in Melbourne. The school posted on Facebook that the community was deeply saddened by her death.

Their deaths were the first confirmed this year on Everest, where favorable weather has allowed hundreds of climbers to reach the summit. The busy season follows two years in which Everest was virtually empty due to disasters.

Phurba said more details were not available because of poor communications with people on the 8,850-meter (29,035-foot) mountain.

Arnold was from Rotterdam, according to his Twitter account, which was updated on Friday with a post that he had reached the summit on his fifth try.

In a local television interview early this year, Arnold said conquering Everest was a childhood dream. "I used to have a poster of Mount Everest above my bed," he told RTV Rijnmond.

Arnold said he was at base camp last year as it was hit by an avalanche caused by a devastating earthquake. The avalanche killed 19 people and injured 61 others and ended the Everest climbing season.

In his interview, Arnold noted that the risks of climbing the world's highest peak did not end at the summit.

"Two-thirds of the accidents happen on the way down," he said. "If you get euphoric and think 'I have reached my goal,' the most dangerous part is still ahead of you."

Strydom and her husband were attempting to climb the seven summits, the highest peaks on the seven continents, in a quest inspired by questions about their vegan lifestyle, according to the Monash Business School's website.

"It seems that people have this warped idea of vegans being malnourished and weak," Strydom was quoted as saying. "By climbing the seven summits we want to prove that vegans can do anything and more."

She had already climbed Denali in Alaska, Aconcagua in Argentina, Mount Ararat in Turkey and Kilamanjaro in Kenya, the post said. Strydom said she felt well-prepared for her attempt to climb Everest, and that depending on whether she reached the summit, her mind would likely turn to her next adventure.

In addition to the two deaths, a 45-year-old woman from Norway, Siv Harstad, suffered snow blindness and was helped down from the summit on Saturday by two Sherpa guides, the Norwegian news agency NTB said.

More than 330 climbers have reached the summit from Nepal since May 11, and several more have done so from the northern routes in Tibet.

The climbing season runs from March through May, after which the monsoon season makes the Himalayan peaks too dangerous.

Thousands of people have summited Mount Everest since it was first conquered by New Zealander Edmund Hillary and Sherpa Tenzing Norgay on May 29, 1953. But more than 250 people have died in the attempt.

Trekking companies were anxious to see foreign climbers return after two years of disasters. The devastating earthquake last year caused the season to be canceled, and climbing attempts were largely abandoned in 2014 after an avalanche above the base camp killed 16 Sherpa guides.