Climbers climb to Camp 2 on the Kinshofer route the day the photographer reveived the last SMS from Alberto Zerain while climbing Nanga Parbat, Pakistan June 24, 2017. Photo: REUTERS

Search team leader Alex Gavan wept uncontrollably after a helicopter dropped him at a Himalayan base camp on June 28, certain an avalanche had killed the two men he was searching for as they tried to conquer Pakistan's "Killer Mountain".

Gavan, a Romanian climber, had abandoned his own efforts to scale the world's ninth-tallest mountain a week earlier to lead the search for Alberto Zerain from Spain and Mariano Galvan from Argentina.

Detailing the desperate search for Zerain and Galvan for the first time to Reuters, Gavan said he had even spoken to them over a satellite phone just a day before they went missing on June 24, when they stopped responding to calls.

The two experienced climbers had chosen a daring route to ascend the 8,126 metre (26,660 feet) Nanga Parbat via the treacherous 13 km (8 miles) Mazeno Ridge, which had been scaled successfully only once before.

However, Gavan became desperate after June 24 when Zerain and Galvan lost radio contact near the ridge, realising that the two men had run out of food.

Rescue efforts were called off after a final helicopter flight over the ridge on July 1. Photographic evidence suggests an avalanche had struck some time in the preceding eight days.

"Just where the avalanche debris is was their last GPS location," Gavan told Reuters, speaking of their last known signal on Mazeno Ridge.

"In the photos you see the tracks of the climbers ... suddenly end at the avalanche fracture line and do not appear anywhere after the fracture line," he said.

Geographically, Pakistan is a hot destination for climbers, but climbing deaths are also common.

It rivals Nepal for the number of peaks over 7,000 metres (22,966 feet) and is home to the world's second-tallest mountain, K2. In all, it has five of the world's 14 summits higher than 8,000 metres (26,247 feet).

However, Pakistan offers other challenges for climbers. In 2012, gunmen dressed as policemen stormed the 4,200-metre (13,780-foot) Nanga Parbat base camp, killing 10 foreign climbers and a Pakistani guide.

ELITE CLUB

Galvan and Zerain both loved climbing. The Spaniard was part of an elite club of climbers who have scaled the world's two tallest mountains, Everest and K2. Galvan climbed Everest in 2012 but an attempt to climb K2 alone and without oxygen ended at 7,300 metres (23,950 feet).

Romania's Gavan said the search for Zerain and Galvan was delayed by a day because they did not have insurance, which meant he had to find the collateral for a rescue mission.

Gavan, who wrote a report on the failed search, said the pictures taken during a second helicopter search on July 1 were conclusive proof that the two men died in an avalanche.

"We looked down the ridge, we looked in the valleys, we looked everywhere, we triple checked," he said.

An eight-member team from the Pakistani mountaineering company Karakorum Expeditions began a new ground search on Friday despite Gavan's evidence.

"The team will search on the Mazeno Ridge of the Nanga Parbat, where the missing climbers are believed to be buried under an avalanche," company spokesman Mehboob Ali said.

Gavan described that operation as "irresponsible", saying it would "only endanger more people's lives".