British nationals Chris Parry and Andrew Bagshaw, who were reported missing in eastern Ukraine, have been killed, their families have said.
Mr Bagshaw, 47, and Mr Parry, 28, were last seen heading to the city of Soledar on 6 January.
Mr Bagshaw’s family said the pair were attempting to rescue an elderly woman when their cars were hit by a shell.
The family of Mr Parry said the men had died while “attempting a humanitarian evacuation”.
Earlier this month, the Russian mercenary group Wagner claimed the body of one of the men had been found.
Soledar had been the focus of intense fighting and earlier this month Russia’s military claimed to have captured the Ukrainian salt-mine time town after a long battle.
In a statement issued by the UK Foreign Office, Rob, Christine and Katy Parry wrote: “It is with great sadness we have to announce that our beloved Chrissy has been killed along with his colleague Andrew Bagshaw whilst attempting a humanitarian evacuation from Soledar, eastern Ukraine.”
Speaking of Mr Parry, originally from Truro in Cornwall, they said: “His selfless determination in helping the old, young and disadvantaged there has made us and his larger family extremely proud. We never imagined we would be saying goodbye to Chris when he had such a full life ahead of him. He was a caring son, fantastic brother, a best friend to so many and a loving partner to Olga.
“Chris was a confident, outward looking and adventurous young man who was loyal to everyone he knew. He lived and worked away as a software engineer but Cornwall was always his home. He loved rock climbing, cycling, running and skydiving and wanted to travel the world.
“He found himself drawn to Ukraine in March in its darkest hour at the start of the Russian invasion and helped those most in need, saving over 400 lives plus many abandoned animals.
“It is impossible to put into words how much he will be missed but he will forever be in our hearts.
“We feel so privileged that he chose our family to be part of.”
Mr Parry and Mr Bagshaw had been in the Donetsk region of eastern Ukraine doing voluntary work.
Scientific researcher Mr Bagshaw was a British national but lived in New Zealand. He had been a volunteer in Ukraine since April.
His parents, Dame Sue and Prof Phil Bagshaw, said the men had been delivering food and medicines and helping the elderly.
In a statement released via news outlets they said Mr Parry and Mr Bagshaw “were attempting to rescue an elderly woman from Soledar, in an area of intense military action, when their car was hit by an artillery shell.
“Andrew selflessly took many personal risks and saved many lives; we love him and are very proud indeed of what he did.”
They added: “The world needs to be strong and stand with Ukraine, giving them the military support they need now, and help to rebuild their shattered country after the war.”
Belgian journalist, Arnaud de Decker, who interviewed the pair three days before they went missing, described the evacuations they were carrying out in Ukraine as “one of the most dangerous jobs you could do right now”.
Speaking on BBC Radio 4’s Today programme, the journalist said Mr Parry had just returned from an evacuation mission and “seemed very experienced”.
“He saved a lot of lives”, said Mr Decker, adding that Mr Parry’s actions were “truly heroic”.
Mr Parry’s last words on camera were “as long as people are willing to be evacuated, I will be ready to go”, Mr Decker told the BBC.
“I think you can only conclude one thing, that’s a very inspiring personality – I’m sure that the family must be very proud of the actions of Chris.”
The Foreign Office has previously warned against all travel to Ukraine, saying there is “a real risk to life”.
British nationals still in Ukraine should leave immediately if it is safe to do so, it said.
Ukraine’s airspace is closed and for those in the vicinity of military activity, the Foreign Office has advised people to stay indoors, away from windows and remain alert to developments.
Mr Parry previously spoke to BBC Radio Cornwall on 2 January from the Bakhmut area in eastern Ukraine.
Explaining his motivation for being there, he said he wanted to help children in particular.
“To be able to get them out of these war-torn areas, it makes it definitely more worthwhile than anything else that I can imagine,” he said.