A helicopter search team has set off to find a British climber who was reported missing on a peak in Pakistan.
Tom Ballard and Italian climber Daniele Nardi last made contact on Sunday, from an altitude of about 20,669ft (6,300m) on Nanga Parbat.
Bad weather and mounting tensions between Pakistan and India had delayed attempts to reach the site.
Ali Sadpara, who has previously scaled the mountain, is understood to be on board the Pakistani army helicopter.
Mr Ballard, originally from Derbyshire, is the son of Alison Hargreaves, who died descending from the summit of K2, the same year she became the first woman to conquer Everest unaided in 1995.
The 30-year-old climber moved to Scotland in 1995 with his sister Kate and grew up near Fort William in Lochaber.
Kate Ballard posted a message on Facebook thanking people across the world for their “love and thoughts”.
“Please join with me in positive thinking that my brother and Daniele will return safe,” she said.
“Please all believe and trust that they will be ok.”
Nanga Parbat is the world’s ninth highest mountain and notoriously difficult to climb.
Stefano Pontecorvo, the Italian ambassador in Pakistan, tweeted on Thursday morning: “Rescue helicopter to search for Daniele Nardi and Tom Ballard is flying and approaching area of Nanga Parbat where they could be.”
It has been reported that weather was poor in the area at the time the pair last made contact.
A number of deaths have earned Nanga Parbat the nickname of “Killer Mountain”.
Mountaineer Sir Chris Bonington said it was a worrying time but that people should not assume the worst.
He said: “One mustn’t write them off, there’s still hope that they are alive and that they are ok, admittedly in very dangerous circumstances.”
Mr Ballard had been living in Italy’s Dolomites mountain range with his father for the last few years and is “regarded extremely highly in the climbing world”, according to online magazine Planet Mountain.
Nanga Parbat has only been climbed in winter once before by experienced Pakistani mountaineer Ali Sadpara.
He is flying to Nanga Parbat to scour the mountain with the Pakistan Army.
A Foreign Office spokesman said they were in contact with Pakistani authorities regarding Mr Ballard’s disappearance.