Five prisoners of war from the UK have returned home from captivity in Ukraine.
A statement published on Wednesday by the foreign ministry of Saudi Arabia, which helped broker the deal, said ten prisoners of war - from the UK, US, Morocco, Sweden and Croatia - had been released.
Since the war began earlier this year, a number of British nationals had been captured in Ukraine – with the Foreign Office working to support the detainees and their families.
Aiden Aslin, a British fighter who was sentenced to death by a pro-Russian court in a separatist area of Ukraine, is among the five Britons back in the UK.
Shaun Pinner, who had previously been sentenced to death alongside Mr Aslin, has also returned home.
Aiden Aslin, from Newark in Nottinghamshire, first went to Ukraine in 2018, where he joined the Marine core. He later became a Ukrainian citizen and has a fiancee living in the country.
Prior to moving to Ukraine he fought with a US backed Kurdish militia against the so-called Islamic State group in Syria.
Sean Pinner's wife is Ukrainian, and, like Aslin, he previously fought in Syria.
The Foreign Office had been working for months to support those detained, while it is believed that Crown Prince of Saudi Arabia Mohammed bin Salman was involved in helping to free the British nationals.
Robert Jenrick, who represents the town of Newark said he was “deeply grateful” to the Ukrainian government, as well as the Saudi Crown Prince and the Foreign Office, for securing the release.
He added: “Aiden’s return brings to an end months of agonising uncertainty for Aiden’s loving family in Newark who suffered every day of Aiden’s sham trial but never lost hope. As they are united as a family once more, they can finally be at peace.”
Robert Jenrick, the MP for Newark, said his constituent Aiden Aslin was among those released by pro-Russian forces - and that his family can 'begin rebuilding' their lives
UK Prime Minister Liz Truss tweeted: "Hugely welcome news that five British nationals held by Russian-backed proxies in eastern Ukraine are being safely returned, ending months of uncertainty and suffering for them and their families."
She thanked Ukrainian president Volodymyr Zelensky “for his efforts to secure the release of detainees, and Saudi Arabia for their assistance”.
UK Foreign Secretary James Cleverly also welcomed the news, clarifying that along with prisoners of war, a civilian had also been released by the Russian forces.
"This brings to an end many months of uncertainty and suffering, including the threat of the death penalty, for them and their families, at the hands of Russia," he said.
Mr Cleverly also highlighted the case of Paul Urey, a British aid worker who reportedly died while being detained by pro-Russia separatists.
“I would like to express my gratitude to President Zelenskyy and his team for their efforts to secure their release, and to HRH Crown Prince of Saudi Arabia, Mohammed bin Salman and his team, for their assistance,” the Foreign Secretary said in a statement.
Further details about the British nationals and the process that led to their release have not yet been shared by the government.
"We just want to let everyone know we're out of the danger zone"
In a video posted to social media Aiden Aslin appeared on a plane alongside fellow former-POW Sean Pinner.
"We just want to let everyone know we're out of the danger zone," Aslin says in the video.
"By the skin of our teeth," adds Pinner.
They went on to thank everyone who had worked to secure their release from a prison in occupied Ukraine.
Hundreds of Ukrainians - including Mariupol defenders - released
Along with the five British nationals, around two hundred Ukrainian prisoners are believed to have been returned by Russia.
Many of those defenders are believed to be members of the Azov regiment, captured in the besieged city of Mariupol in May.
In return, Ukraine handed over one man, a 68-year-old oligarch named Viktor Medvedchuk. It's thought that President Putin is godfather to his daughter.
In another swap, Ukraine gained the release of five more citizens in exchange for 55 Russian prisoners it was holding, Ukraine's President Zelenskyy said.
Zelenskyy added that released officers, including Azov Regiment commanders Denys Prokopenko and Svyatoslav Palamar, are in Turkey, where they will remain as part of the deal “in complete safety” until the end of the war, under the protection of Turkey's President Erdogan.
UN Secretary-General Antonio Guterres welcomed the exchanges, calling them “no small feat,” but adding that “much more remains to be done to ease the suffering caused by the war in Ukraine,” his spokesman said.
The first lady of Ukraine, Olena Zelenska, tweeted her happiness after the release was confirmed.
"The thoughts and joy of millions of Ukrainians are with them today. We are grateful," she wrote.
The first lady is currently at a meeting of the UN General Assembly in New York. Her husband received a rare standing ovation after he gave a video address to delegates.
US Ambassador says thoughts are with released POWs
The US Ambassador to Ukraine, Bridget Brink, said two US citizens were among the POWs released by Russian forces overnight.
In a tweet she thanked the Ukrainian President and said her thoughts were with the released captives.
The White House national security advisor echoed her sentiments, and thanked "the Crown Prince and Government of Saudi Arabia for facilitating.
"We look forward to our citizens being reunited with their families."
He also praised Turkey for its role in negotiating the prisoner exchange.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know