Anton Spitsyn, who led one of the battlegroups of the Omega special forces, part of the National Guard, died of wounds sustained during a combat mission, Spitsyn's brother, Oleksandr, wrote on Facebook on Feb. 3.
Spitsyn was one of the co-founders of the unit, called the Peaky Blinders after the British crime drama series of the same name. Spitsyn's unit is currently defending Kharkiv Oblast.
Spitsyn had served in Ukraine's National Guard since the first days of the full-scale invasion launched by Russia on Feb. 24, 2022.
"Today is the darkest and hardest day of my life. Today my brother left me. He was the closest and dearest person to me," Oleksandr Spitsyn wrote.
"He lived as a hero and died as a hero."
Anton Spitsyn was born and raised in Kharkiv Oblast. Prior to the full-scale invasion, he owned a construction business and was involved in charity work, particularly teaching English to orphans for free, the Omega special forces statement read.
Moscow's forces have ramped up pressure in Ukraine's east as Ukrainian troops find themselves increasingly outnumbered and outgunned.
Russian forces have been attempting to force the Oskil River in Kharkiv Oblast for months in an attempt to outflank Ukrainian soldiers.
Andrii Besedin, head of the Kupiansk town military administration, said on Jan. 9 that Moscow's troops are trying to secure a bridgehead in the town of Dvorichna on the river's Ukraine-held western bank.
Besedin also said that Russian forces are now within 2 kilometers (1.5 miles) of Kupiansk's outskirts, adding that the situation is "very difficult."