(CNN) - Three more climbers have died on Mount Everest, bringing the toll of those dead or presumed dead to nine across the 2019 climbing season.
Two people died on the Nepali side of Everest earlier this week, Meera Acharya, director of Nepal's department of tourism, confirmed to CNN.
Nepali climbing guide Dhruba Bista fell ill on the mountain and was transported by helicopter to the base camp, where he died Friday.
The following day, British climber Robin Haynes Fisher died of what appeared to be altitude sickness at 8,600 metres (28,215 feet), while descending from the summit.
Irish climber Kevin Hynes, 56, died Friday morning on the Tibetan side of Everest in his tent at 7,000 meters (22,966 feet), the UK Press Association reports. Hynes, a father of two, was climbing with a group from the UK-based company 360 Expeditions.
Hynes reached 8,300 meters on Wednesday, but turned back the following day, accompanied by experienced climbing guide Dawa Sangee.
In a statement, 360 Expeditions called Hynes "one of the strongest and most experienced climbers on our team," adding, "He really was a wonderful man and it was a great privilege to have him on our team."
Earlier this week, crowds of climbers became stuck in a queue to the summit, above the mountain's highest camp at 8,000 meters (26,247 feet). Two died Wednesday after descending from the summit: Indian climber Anjali Kulkarni, 55, and American climber Donald Lynn Cash, 55.
Kalpana Das, 49, and Nihal Bagwan, 27, both from India, also died on Everest this week. Both died Thursday on their return from the summit.
Ravi, a 28-year-old Indian climber who goes by one name, died the previous week on May 17.
Anjali Kulkarni, who had become stuck in the "traffic jam," died on her way back from the peak. She had more than 25 years of climbing experience and had previously climbed Mount Kilimanjaro in Tanzania and Mount Elbrus in Russia, her son Shantanu Kulkarni told CNN.
Kulkarni spent six years training for her Everest climb. Previously, she owned an advertising agency with her husband, but they both retired to "pursue their dream of standing atop Mount Everest," Shantanu said.
Cash, a grandfather, collapsed near a portion of the trail that had an altitude of about 8,770 meters (28,700 feet), according to the Nepali expedition company Pioneer Adventure Pvt. Ltd.
"Our team did their best to save his life," the company said, adding that Sherpa guides had attempted to keep him alive while pulling him down the mountain. "Despite their best efforts in providing the best guidance, sufficient oxygen supplies and medical support they could not save his life."
Danduraj Ghimire, director general of Nepal's Tourism Department, said suggestions that the deaths of Kulkarni and Cash were related to the heavy traffic at the summit were "baseless."
"The weather has not been very great this climbing season, so when there is a small window when the weather clears up, climbers make the move," Ghimire said. "On May 22, after several days of bad weather, there was a small window of clear weather, when more than 200 mountaineers ascended Everest. The main cause of deaths on Everest has been high altitude sickness which is what happened with most of the climbers who lost their lives this season as well."
Last week, a search for Irish climber Seamus Lawless, 39, was called off, after the Trinity College Dublin professor fell while descending from the peak, according to PA.
In a statement, a spokesperson for the university said: "While the experienced search team has made every effort to locate Shay, the extremes of operating at high altitude and the sheer range of the search area ultimately proved too difficult and based on expert advice the Lawless family have decided to call off the search rather than risk endangering anyone's life in the treacherous conditions."
The death toll for Everest's 2019 climbing season is not unusual for the mountain. In 2018, five climbers died, while six died in both 2017 and 2016.