A newly released video shot by one of the eight hikers who died while trying to scale India’s second highest mountain in May depicts the grueling conditions the climbers faced before they apparently perished in an avalanche.

The footage, released late Monday by the Indo-Tibetan Border Police, was discovered on a GoPro camera carried by one of the hikers. It was found at 19,000 feet in the Himalayas, in the area where seven of the eight bodies of the hikers were recovered.

The climbers — four Britons, two Americans, one Australian and one Indian — disappeared in May while attempting to reach the previously uncharted peak of Nanda Devi, India’s second-highest mountain at 21,250 feet.

The 1:55 minute video shows two clips of the group atop an unnamed peak close to Nanda Devi East. The first segment depicts the climbers checking their equipment by headlamp before the camera pans to the rising sun silhouetting the ridge line ahead. The second portion shows seven of the climbers walking slowly in a single-file line along a crest in bright daylight, the sound of heavy breathing and wind in the background.

Led by British mountain guide Martin Moran, the group had set out on May 13. From their second base camp at nearly 16,000 feet, the team posted an upbeat message on May 22: “A first ascent is a creation in the same sense as is a painting or a song.”

But after an apparent avalanche on the mountain, communication lines went silent on May 26. Panic set in on May 31 when they did not return to the base camp as expected.

An aerial search and rescue team first spotted several of their bodies on June 3, but difficult weather prevented authorities from recovering them. Border police then sent a rescue mission on foot to retrieve the bodies — an operation that took about 500 hours over 20 days, according to Indo-Border Tibetan Police force spokesman Vivek Kumar Pandey.

Authorities successfully recovered all but Moran’s body, which remains missing.

“This was a historic body retrieval mission at 19,000 feet altitude. It’s unprecedented,” Pandey said. “It was also challenging emotionally to find their belongings.”

To ensure that the bodies did not decompose, the rescue team would often have to cover them in snow. Pandey said that the operation was risky given the frequent avalanches in the region.

Border patrol officers recovered the video footage published Monday from a memory card inside a broken GoPro they found among the bodies. They said the video may have been shot on the night of May 25 and the early morning of May 26. It’s the last visual record of the group alive.

A rope connects the climbers as they walk along the ridge in the latter half of the video, with the cameraman in the back of the human chain. Gingerly placing one foot in front of the other, the climbers advance along the snow-covered mountain, digging ice picks into the ground before the video cuts out.

Pandey said it is possible that a snow cornice — an unsupported ledge of snow usually jutting out from a ridge — broke underneath the climbers, causing them to lose control and fall. Snow cornices are especially prone to breaking during avalanches.

Apart from Moran, the Britons in the group included John McLaren, Rupert Whewell and Richard Payne. The Americans were identified as Missouri native Anthony Sudekum, 63, and Ronald Beimel, 34, from Los Angeles, according to the New York Post. Rounding out the group were Australian Ruth McCance and Indian guide Chetan Pandey.

Masih reported from New Delhi.