More deaths on Everest

The world's highest mountain claimed more lives over the weekend in one of the deadliest episodes on Everest in three years.

Australian Francesco Enrico Marchetti, 54, died from apparent altitude sickness on the Tibetan side of the mountain, according to local media. Marchetti had reached about 8,300 meters (27,230 feet) above sea level when taken ill. He died while being brought down to a lower camp, according to Navin Trital of the Expedition Himalaya company that coordinated logistics for the climber.

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The Slovak climber Vladimir Strba, 50, died near the Balcony on the Nepali side just a few hundred meters from the summit. He had reached the so-called "death zone" above the 8,000-meter mark, a part of the mountain notorious for its difficult terrain and thin air.

A spokesman for Nepal's Tourism Department said the circumstances leading to Strba's death were not clear.

The "death zone" also claimed the life of 50-year-old American climber Roland Yearwood. Again, the exact circumstances of his death are not known.

Unfavorable conditions

All three climbers died on Sunday. Their deaths bring the toll for this month to at least five, with a further climber, Ravi Kumar from the Indian state of Uttar Pradesh, still missing after falling sick on his way back from the summit. Kumar's Nepalese Sherpa guide managed to make it down to the nearest camp, though he too was sick and had frostbite, according to Thupden Sherpa of Arun Treks and Expedition.

More than a dozen climbers in difficulties have been rescued from the mountain in the last three days, helicopter rescue operators say.

The current spring climbing season, which began in March and runs through this month, has been hit by unpredictable weather, strong winds and unusually cold temperatures.

On April 30, famed Swiss climber Ueli Steck died while on an acclimatization climb, and 85-year-old Min Bahadur Sherchan of Nepal died at base camp earlier this month while trying to reclaim his title as the world's oldest person to summit Everest.

Major feature collapses

One of the most notable and challenging features of the climb to the summit, the Hillary Step, a nearly vertical rock face, is meanwhile reported to have collapsed.

The Step was named after Sir Edmund Hillary, who with Nepalese Sherpa mountaineer Tenzing Norgay achieved the first confirmed successful scaling of the summit in May 1953.

Hundreds of climbers

The Nepalese Tourism Department has issued a record 371 permits this for people to scale the 8,848-meter (29,030-foot) mountain, while nearly 200 climbers went from Tibet. Hundreds are still waiting to summit before the climbing season ends with the monsoon in early June.

More than 200 climbers have so far successfully summited Everest this season from the two sides.

Last year, five climbers died on the mountain, while a total of 640 people summited from both sides.

In another deadly episode three years ago, an avalanche swept through base camp, killing 18.

 tj/rt (Reuters, AP, AFP)