A Pakistan army helicopter flew to rescue frost-bitten survivors from the slopes of K2 on Monday, leaving behind at least 10 dead climbers and more missing after an ice fall near the top of the world's second highest mountain.
"We sent a helicopter to rescue six people, including four Dutch and two Italians," said Major Farooq Firoz, an army spokesman in Gilgit, the main town in Northern Pakistan.
"They are at different spots at altitude of about 5,500 meters (18,000 feet)."
Accounts differ, but Sher Khan, a retired colonel and vice president of the Alpine Club of Pakistan, said that aside from nine international climbers a Pakistan high altitude porter had also died, and at least three more were missing, including another porter.
Hopes of finding them alive were faint, as they had been stranded at an altitude known as the "Death Zone" after an ice wall collapsed and tore away the fixed lines they were relying on to return after summiting the 8,611 peak on Friday.
"On K2, when they're missing they're dead," said Khan, one of Pakistan's most experienced climbers.
Several teams had massed on the peak for an assault on the summit. At least two climbers died during the ascent, then disaster struck during the descent at a steep gully known as the Bottleneck, above 8,200 meters.
The ice fall killed three Korean and two Nepali climbers, and left around a dozen more stranded above the Bottleneck, exhausted in the oxygen-starved air.
One survivor, Swedish climber Fredrik Strang, described to U.S. broadcaster CNN how people "froze to death" during the night.
He also spoke of a mounting sense of foreboding after a Serbian climber and a Pakistani fell to their deaths during the ascent on Friday.
Anxious fellow climbers keeping vigil at K2 base camp on Monday spotted two men through the clear morning air edging down the steep flanks of the towering pyramid of rock and ice.
They identified the two as Dutch climber Wilco van Rooijen and Italian Marco Confortola, who along with another climber were believed to have traversed the Bottleneck without fixed lines.
The deaths of a Norwegian and a French climber from the same team had already been confirmed, while an Irish climber, Gerard McDonnell, was still missing.