Seven people died while climbing Mount Everest this week.
On Thursday, Indians Kalpana Das, 52, and Nihal Bagwan, 27, died while descending from the peak, and an Austrian climber died on the North side of the mountain, the BBC reported.
Bagwan’s tour guide told AFB he had been “stuck in the traffic for more than 12 hours and was exhausted.”
The two who died on Wednesday were identified as Indian Anjali Kulkarni and American Donald Lynn Cash.
Kulkarni’s son told CNN she died on her way back from the summit of the mountain to the camp, during a traffic jam.
Cash reportedly fainted from altitude sickness. His daughter told NBC’s Today Show that a cause of death has not been officially determined, but that family members believe he suffered a heart attack.
Another climber, Irishman Seamus Lawless, went missing on May 16 and is presumed dead.
On Wednesday a picture posted by climber Nirmal Purja shows hundreds of people in a winding line up to the top of the mountain.
Nepalese officials say the weather was the main reason for the traffic queue.
“There are explanations for the increase in traffic of climbers on Mount Everest,” said Danduraj Ghimire, chief of Nepal’s department of tourism. “The first reason is the weather, of which there were only a very few windows of good conditions for the climbers to attempt reach the summit.
“The weather conditions have forced climbers to be stacked in the base camp for longer periods of time. There was clear weather on the mountain for only a very few days, which is when all the climbers waiting eagerly at the base camp made their attempt to the summit. That was the main reason for the traffic jam at Everest.”
Ghimire noted that there are no rules limiting the number of people allowed on the mountain.
Four other people have died on the mountain earlier this year, the Press Trust of India reports.
— With files from the Associated Press
WATCH: (2016) B.C. woman shares experience climbing Mt. Everest