Masked gunmen killed at least 10 people working for a British mine-clearance charity when they raided their camp in northern Afghanistan.
The Halo Trust said an unknown armed group had attacked a camp in Baghlan province shortly before 10pm on Tuesday evening, shooting staff dead in their beds after a day's work.
The UK-American charity, which has offices in Dumfries, Wilton and Washington DC, said 10 staff, all of them Afghans, had been shot dead. Another 16 were wounded.
The trust has been working in Afghanistan since 1988, removing mines and munitions which have been left behind by more than 42 years of fighting.
James Cowan, the former British Army major general who now runs the charity, said the trust would continue its work, despite suffering the worst attack in its history.
He said he told the BBC the attackers had gone “bed-to-bed, murdering in cold blood my staff”.
“Ten of my people were killed and 16 were badly wounded. My thoughts are obviously very much with the families and the loved ones of the bereaved and wounded.
“This is a horrific incident, the worst in the Halo Trust's history. It's very sad, but we are here for Afghanistan. We were in Afghanistan many years before 9/11 and we will be here many years after the international withdrawal.”
The Afghan government immediately blamed the Taliban for the attack. Baghlan province has seen heavy fighting in recent months, with near-daily battles between the Taliban and government forces in several districts.
A Taliban spokesman denied any involvement however. "We condemn attacks on the defenceless and view it as brutality," Zabiullah Mujahid said on Twitter. "We have normal relations with NGOs, our Mujahideen will never carry out such brutal acts."
A survivor told AFP that five or six armed men scaled the camp's compound walls and gathered everyone, asking if there were any members of the Hazara ethnic minority present. "Nobody responded," said the survivor.
The gunmen singled out and shot the compound leader, then said 'kill them all'. Afghanistan's Hazara people, who are largely Shia Muslims, have been repeatedly targeted by the local branch of Islamic State group.
Mr Cowan said he would not speculate on who carried out the attack, but pointed to the Taliban denial and said a local band of the insurgents “came to our aid and scared the assailants off”.
The United Nations condemned the "heinous attack". Ramiz Alakbarov, the secretary general's special representative, said: "It is repugnant that an organisation that works to clear landmines and other explosives and better the lives of vulnerable people could be targeted."
Afghanistan's long conflict has meant swathes of countryside have been mined over the past four decades. De-mining agencies like Halo have had great success clearing parts of the country, but the work is dangerous. As well as the risk of mines, workers are regularly kidnapped or threatened in local disputes, by local criminals or by insurgents.
The trust was heavily supported by Princess Diana and the Duke of Sussex has also been a patron of its work. The charity rose to prominence in 1997 when Diana, Princess of Wales, visited a minefield in Angola being cleared by Halo shortly before her death. The photograph of the princess in the minefield remains one of the most famous images of her.