(CNN) Four people have died in the span of four days on Mount Everest including a Sherpa, while two others have gone missing.
Danger is inherent in climbing the world’s highest peak. And there are fatalities — there has been at least one every year since 1990, according to the country’s tourism department. And more than 200 climbers have died since Tenzing Norgay and Edmund Hillary made the first official ascent in 1953.
But the recent deaths — coming so quickly on the heels of one another — has rattled climbers who are now beginning their descent as the climbing season comes to an end.
April was the first month of climbing since all ascent was halted after the catastrophic earthquake that struck Nepal in 2015 and a deadly avalanche that killed 16 Sherpas in one day in 2014.
Crew member Phurba Sherpa (no relation to the journalist of the same name) fell to his death. The 25-year-old had been working to fix a route about 150 meters near the summit when he fell, according to Mingma Sherpa, the Nepal rescue team leader who was at the Everest Base Camp.
Eric Arnold, 36, of the Netherlands died at night while heading back after a successful summit on Everest, according to Tashi Lakpa Sherpa, the owner of Seven Summit Treks. A heart attack was suspected, he said.
Arnold was a triathlete based in Rotterdam, according to his Twitter bio.
An Australian woman Maria Strydom who was also traveling with the Seven Summit Treks started suffering altitude sickness. She had reached Camp IV, the final camp before the summit.
Strydom, 34, could not move upward anymore, and a rescue attempt to reach her failed, according to Tashi Sherpa. The finance professor at Monash Business School in Australia died Saturday before she could come back down to Camp III.
Subash Paul, 44, died at Base Camp II from altitude sickness, according to Wangchu Sherpa, Managing Director of Trekking Camp Nepal.
Paul was part of a team (consisting of four Indian climbers and four Sherpas) that also saw two members — Paresh Chandra Nath and Goutam Ghosh — go missing Saturday night.
“It is not clear what happened. We believe the weather suddenly deteriorated at some point, and the team lost direction,” Wanchu Sherpa said.
An official at Nepal Tourism Department Gyanendra Shrestha said a helicopter search was not possible because they were too high up the mountain.
“We are trying to communicate with other expedition teams around that level to locate the missing climbers,” Shresthra said.
The fourth climber from the team, Sunita Hazra, was rescued and is undergoing treatment at base camp.
Since climbing season opened on Everest, about 300 people have scaled, according to data from Everest Base Camp as of Saturday.
The risks are well-known as more than 250 people have died on the mountain.