By Mattea Bubalo and Bethany Bell
K2 - the world's second tallest mountain - is regarded as one of the most challenging and dangerous to climb. Photo: Joe Stenson / AFP
A well-known Norwegian mountaineer has denied accusations that her team climbed over an injured guide during a bid to break a world record.
The porter, named as Mohammed Hassan, had fallen off a ledge on Pakistan's K2 - the world's second-highest mountain.
Video on social media appears to show a group walking by Hassan, who reportedly died a few hours later.
But Kristin Harila told the BBC she and her team tried everything to help him in dangerous conditions.
"It's a tragic accident... here is a father and son and a husband who lost his life that day on on K2. I think that's very, very sad that it ended this way," she said.
The Norwegian was heading for K2's summit to secure a world record and become the fastest climber to scale all peaks above 8,000m.
During the ascent on 27 July, Hassan reportedly fell from an extremely narrow path known as a bottleneck.
Two climbers, Philip Flämig and Wilhelm Steindl, who is from Austria, have posted pictures appearing to show people climbing over him. It is unclear what point of the incident the images purport to show.
The pair were also on the mountain that day, but had cancelled their ascent because of dangerous weather conditions and an avalanche. They had been filming for a documentary about Steindl's attempt to reach the summit.
As their camera display was small, they say they only saw the details of what their drone captured the next day.
"We saw a guy alive, lying in the traverse in the bottleneck. And people were stepping over him on the way to the summit. And there was no rescue mission," Steindl told the BBC.
"I was really shocked. And I was really sad. I started to cry about the situation that people just passed him and there was no rescue mission."
Hassan was being treated by one person "while everyone else" moved towards the summit in a "heated, competitive summit rush", Flämig told Austria's Der Standard newspaper.
Harila, however, has denied the accusations that Hassan was left to die.
Mohammed Hassan's death was a tragic accident, says Kristin Harila. Photo: Hassan family
Speaking to the BBC's The World Tonight programme, Harila said members of her team tried to help Hassan but it was "not possible" to get him back down the narrow route, which was crowded with other climbers.
She said Hassan was "not part of our team" and she had not seen him fall, but that he had not been left alone once the larger group realised he was hurt.
Harila suggested there were questions to answer for the company that employed Hassan - who was part of a "fixing" team sent ahead of the climbing group to secure ropes - because he appeared not to have an oxygen supply or suitable cold weather clothing.
She added: "We were trying to save him, we did everything we could for many hours... it's a very, very narrow path.
"How are you going to climb and traverse and carry [a person]? It's not possible."
Kristin Harila (C) set a record to become the fastest climber to scale all peaks above 8,000m. Photo: Sanjit Pariyar / NurPhoto via AFP
In an earlier Instagram post describing what happened, the Norwegian climber said she had been walking when she saw the other team Hassan was part of a few metres ahead before the "tragic accident" happened.
She said no-one was to blame for his death, adding that she had decided to make the statement to stop the spread of "misinformation and hatred".
Harila said she did not see exactly what took place, but the next thing she knew, Hassan "was hanging upside down" on a rope between two ice anchors, with his harness "all the way down around his knees. In addition, he was not wearing a down suit and his stomach was exposed to snow".
Her team tried for an hour-and-a-half to fasten a rope to the guide and give him oxygen and hot water, she recounted, until "an avalanche went off around the corner".
Having established her team were safe, she said she understood more help was coming and decided to move forward to avoid overcrowding on the bottleneck. Her cameraman stayed behind to help until he himself ran low on oxygen.
"It was only when we came back down that we saw Hassan had passed and we were ourselves in no shape to carry his body down."
She did not say if anyone was with the injured porter when her cameraman left, or when they passed his body upon their descent.
K2, along the Pakistan-China border, stands at 8,611m (28,251ft) and is regarded as one of the most challenging and dangerous mountains to climb.
- This story was first published by BBC.