The UK has confirmed its first war death in Ukraine — a former British soldier who reportedly fought the Russians in the Donbas

• The UK has confirmed the first death of a British national in the war in Ukraine.
• He's thought to be Scott Sibley, 36, a former British soldier who volunteered to join the war.

The UK Foreign Office said on Thursday that a British citizen had been killed in Ukraine and another has gone missing — the first time that a Briton was confirmed to have died in the war.

According to multiple media reports, the deceased is thought to be Scott Sibley, a former British soldier who served in the Royal Logistics Corps and volunteered to fight for Ukraine.

Authorities did not officially identify either party nor has it been confirmed why they were in Ukraine.

However, a spokesperson for the Foreign Office said it is providing support to both of their families, per Reuters. The spokesperson also said that the UK is "urgently seeking further information" on the missing Briton.

Citing unnamed diplomatic sources, the BBC reported that Sibley, 36, and the missing man were likely fighting alongside Ukrainian forces in Mariupol or the Donbas region.

Tributes for Sibley have emerged on Twitter and Facebook. A post on the Facebook page "Logistic Support Squadron" said Sibley was a "former serving soldier" and that he "showed Commando spirit until the end."

A photo circulating on social media appears to show Sibley with a Ukrainian flag on his left shoulder.

—Illia Ponomarenko (@IAPonomarenko) April 28, 2022

Meanwhile, a GoFundMe page for Sibley's funeral said he died on April 23 and described him as a "friend like no other."

"His life may have been cut short but he lived to the full and did things the Sibs way, right until the end," wrote poster Craig Gant, who has raised close to $12,000.

An unknown number of British nationals have volunteered to fight for Ukraine against Russia's invading forces.

In mid-April, two British volunteers who joined the Ukrainian marines, Aiden Aslin and Shaun Pinner, surrendered to Russian forces in Mariupol after they ran out of ammunition.

They later appeared on Russian media, asking UK Prime Minister Boris Johnson to free them in exchange for Viktor Medvedchuk, a pro-Russia Ukrainian politician and ally of Russian President Vladimir Putin.

Three UK special forces members are also believed to have been killed in a Russian airstrike on a base close to the Ukraine-Poland border. However, the UK authorities have not confirmed the deaths.