A British man who summited Mount Everest wrote that he feared the dangers of overcrowding on the world's highest peak before dying on his descent.

Robin Haynes Fisher, 44, is among the growing number of people who have died trying to conquer the Himalayan summit this climbing season, putting a spotlight on the crowds of mountaineers that are making the ascent and descent even more treacherous.

He died Saturday at 8,600 meters (around 28,200 ft) above sea level after feeling ill, Meera Acharya, director of Nepal's department of tourism, told the Himalayan Times.

"He was 150 metres below the summit when he suddenly fell down," said Murari Sharma of Fisher's expedition company. "Our sherpa Jangbu tried to wake him up him and change his oxygen bottle and tried to give him some water but there was no response."

In a foreboding post on Instagram last week, Fisher shared his condolences for two climbers who died in the "death zone" above the 8,000-meter (around 26,000-ft) mark in the days leading up to his expedition. He noted that around 100 climbers attempted the summit in the two days that those deaths occurred.

"With a single route to the summit delays caused by overcrowding could prove fatal," Fisher said.

Around 700 people were attempting the challenging climb to the peak in the past week, Fisher said, adding he planned to delay his own attempt of the summit to May 25 in hopes there would be fewer people.

"Unless of course everyone else plays the same waiting game," he said.

Delays in reaching the top expose climbers to greater risks of altitude sickness and frostbite.

Three Indian nationals died Thursday while trying to climb Everest, which sits on the border of Nepal and Tibet, an autonomous region of southwest China, officials and mountaineering agencies confirmed to NBC News on Friday.

An American man from Utah died earlier in the week after having reached the summit and fulfilling his life’s dream, his children told NBC affiliate KSL-TV. Don Cash, 55, was a passionate climber who had left his job to join the Seven Summits Club — whose members attempt to summit the highest mountain on every continent.

The British broadcaster and adventurer Ben Fogle, the U.N. patron of the wilderness, tweeted a photo of the long lines near the top and called on the countries that share Everest to limit the number of climbers on the mountain, suggesting instead a marathon-style lottery system for climbing permits.

As of May 19, the Nepalese Tourism Department said it had provided 381 permits to climb Everest.

Expeditions can cost tens of thousands of dollars, according to the British Mountaineering Council. A total of 560 people reached the summit of Everest last year, according to Nepal's tourism director Acharya.

Since Edmund Hillary and Tenzing Norgay became the first people to reach the summit of the mountain in 1953, attempting the 29,029-ft peak has become more and more popular.

“Before you reach the summit, you have to wait and every minute counts at the height,” said Krishma Poudel of Peak Promotion, a mountaineering agency in Nepal.

“Waiting for hours at that kind of height really takes a toll,” she added.