A Ukrainian soldier reportedly blew himself up on a bridge to prevent a line of Russian tanks from crossing.
The General Staff of the Armed Forces of Ukraine announced the act of bravery by Vitaly Skakun, who was part of a marine infantry battalion aiming to block the Henichesk bridge in the southern Kherson region.
As the tanks approached, Mr Skakun jumped in to carry out a mission to blow up the bridge.
“The bridge was mined, but he didn’t manage to get away from there,” the military said in a statement.
“According to his brothers in arms, Vitaly got in touch [with them] and said he was going to blow up the bridge. Immediately after an explosion rang out.”
“His heroic act significantly slowed down the push of the enemy, allowing the unit to relocate and organize defense.”
Officials said they were working on awarding Mr Skakun with posthumous honors.
The statement concluded: “Russian invaders, know, under your feet the earth will burn! We will fight as long as we live! And as long as we are alive we will fight!”
Mr Skakun’s bravery came hours before Russian tanks descended on Kyiv as Ukrainian President Volodymyr Zelensky urged residents of the capital city to arm themselves with Molotov cocktails and fight back against the invasion.
Meanwhile, Russian President Vladimir Putin called on the Ukrainian military to seize power in their country and overthrow Mr Zelensky.
US defence officials have said the advancement toward the heart of Kyiv has moved slower than Russia anticipated.