A swiss and an American climber died on Mount Everest in the year's first causalities, expedition organizers said on Thursday.

41-year-old Abdul Waraich from Switzerland and a US National Puwei Liu, 55 are reported to be the first causalities of the season.

“Abdul successfully reached the summit but began experiencing issues during his descent,"  Chhang Dawa of the expedition organizer, Seven Summit Treks said. “We sent two additional Sherpas with oxygen and food. Unfortunately, the Sherpas couldn’t save him."

 Liu, on the other hand, had reached the climbing feature named the Hillary Step, located between South Col and the summit. However, he had to return following snow blindness and exhaustion.

With the help of support team members and additional oxygen, he was brought back to the camp at South Col but died on Wednesday evening, the organizers said.

No other details were given on the dead climbers and when their bodies would be brought down. Bad weather conditions have forced climbers to descend to lower altitudes for now.