KATHMANDU: At least four climbers including a woman mountaineer were found dead inside their tent at a high altitude camp on Mt Everest taking the death toll on the world’s highest mountain in the spring climbing season to at least nine in Nepal side, the base camp officials have confirmed.

Expedition officials told THT on Wednesday morning that Sherpa climbers spotted four bodies – two Nepalis and two foreigners – at camp IV on Tuesday while they were searching for another body to recover.

Sherpa climbers from Seven Summit Treks who were there to recover the body of a Slovak mountaineer spotted four more dead bodies inside a tent, Managing Director at Seven Summit Treks Mingma Sherpa quoted the rescuers as saying over the phone from the incident site. Though the precise details of the incident are not available yet, the cause of death could be suffocation inside the tent, the rescuers reported.

At least six Sherpa climbers were there to recover the body of 49-year-old Slovakian solo climber Vladimir Strba who died at Camp IV on Sunday afternoon, he said, adding that Slovak’s body was being brought to Camp II.

Multiple sources at the base camp also confirmed that four persons belonging to a new trekking company have gone out of contact since Sunday after they were last seen near the Balcony area. “We are trying to verify all shreds of evidence before naming the victims,” a liaison officer at the Ministry of Culture, Tourism and Civil Aviation said.

Earlier, an American climber Roland Yearwood died of altitude sickness near South Col on Sunday while Sherpa climbers recovered the body of Indian climber Ravi Kumar on Mt Everest on Monday. Octogenarian mountaineer Min Bahadur Sherchan died at the base camp of Mt Everest on May 6 while famed Swiss climber Ueli Steck had lost his life in an accident in the Mt Everest region on April 30.