A Canadian climber passed away above Camp III on Mt Everest on May 25, taking the season's death toll to 12, officials said. Five more are feared dead on Everest with at least three foreign and two Nepali climbers missing in the high camps for many days.

Petrus Albertyn Swart from Canada died after he fell ill above Camp IV, said base camp sources. The Vancouver-based climber suffered from high altitude sickness while heading for the summit push and was helped to descend to Camp IV, sources said, adding that he died on his way to Camp III. The climber was part of an expedition managed by Madison Mountaineering.

Mt Everest has recorded 12deaths this spring season. At least five climbers are still missing above the high camps.

Solo Hungarian climber Suhajda Szilard went missing from the Hillary Step after attempting to scale Mt Everest without supplemental oxygen or personal sherpa support on May 24. A team of sherpa rescuers along with a helicopter are searching for him.

Deaf and mute Malaysian Hawari Bin Hashim, 33, has been missing since May 18 when he arrived at Camp IV from the summit point, while Shrinivas Sainis Dattatraya, an Indian-Singaporean climber, went missing from 8,500m on Mt Everest.

Dattatraya reportedly fell from 8,500 metres into the Tibetan side. Efforts are still on to search for missing climbers.

Meanwhile, Janakpur-based Ranjit Kumar Shah and his Sherpa guide Lakpa Nuru Sherpa have been out of contact from the South Summit since May 25.

The duo's GPS was last tracked near South Summit at around 1:00am, sources said.

Earlier, Ang Kami Sherpa, a kitchen staff at Camp II, died on May 21 after a fatal fall at a helipad when collecting logistics.

Forty-year-old Jason Bernard Kennison from Australia breathed his last while returning from the summit point on May 19.

Malaysian police Ag Askandar Bin Ampuan Yaacub died above South Col while climbing Mt Everest on May 19. Sherpa climbers are on the way to the high camp to recover his body.

Xuebin Chen, 52, died near south summit on Mt Everest while heading for the summit push on May 18.

An Indian woman Suzanne Leopoldina Jesus, who fell ill at the Mt Everest base camp, also died in Lukla while undergoing treatment on May 18.

Victor Brinza from Moldova died after he fell ill at South Col on May 17.

Phurba Sherpa from Sankhuwasabha died near Yellow Band above Camp III on May 16.

American Doctor Jonathan Sugarman, 69, died during acclimatisation rotation at Camp II on May 1.

On April 12, Dawa Tseri Sherpa, Pemba Tenzing Sherpa, and Lakpa Rita Sherpa were buried in an avalanche that struck an icefall route above base camp.