Eight climbers believed to be dead on a treacherous Himalayan mountain “knowingly risked” their lives by changing their plans without permission, an Indian official said on Tuesday.

Military helicopters involved in a major search for the four Britons, two Americans, an Australian and an Indian on Monday spotted five bodies on the Nanda Devi mountain.

The group, led by highly experienced British climber Martin Moran, had been given permission last month to scale the eastern peak of the mountain.

But Moran’s mountaineering company announced on Facebook on May 22 after reaching a second base camp that they planned to attempt “an unclimbed peak” 6,477m high.

“This mountain range is more difficult to scale than Mount Everest. They knowingly risked their lives after changing their plans without informing the authorities,” said an official in Uttarakhand state, where the mountain range is located.

“The permission was granted for Nanda Devi east and any diversion is illegal. We were completely unaware of their changed plan and that turned fatal,” he said, preferring to remain anonymous.

Dangerous operation

Surendar S Panwar from local trekking operator Cosmos Tour and Expedition, said Moran was highly experienced and had previously climbed in the area.

“It is quite surprising how a qualified mountaineer like him made a mistake,” Panwar said.

Vijay Kumar Jogdande, a local magistrate, said on Tuesday that a plan was being devised to retrieve the bodies in what would be a dangerous operation due to the risk of avalanches and bad weather.

“We are meeting today to chalk out a plan to retrieve the bodies,” said Jogdande. Officials were looking at the possibility of sending a team on foot or airlifting the bodies.

He said the aerial pictures shot on Monday showed four bodies together and another lying buried at a distance on a ridge that was swept by an avalanche. Three more were believed to be nearby.

Officials said a total of 12 climbers had set out from Pithoragarh district’s Munsiyari village but they separated into two groups a week later after reaching the Nanda Devi east base camp.

The groups communicated last on May 26, a day before heavy snowfall and massive avalanches hit the heights.

Later the eight failed to report back to the base camp, first prompting a search by the other four climbers followed by a massive search by Indian authorities after a porter sounded the alarm.