Alex Ryzhuk was born in Dublin to Ukrainian parents and lived in the Rathmines area of the city. He travelled to Ukraine last year to join the military.
Mr Ryzhuk is missing in action and presumed dead. The Department of Foreign Affairs has confirmed it is aware of the case and is providing consular assistance.
He was interviewed recently by Irish filmmaker Finn Boylan of FinnHouse Films as part of coverage broadcast on Prime Time on 8 August about developments in the war, his personal experiences on the frontline and his own background growing up in Ireland.
News about rape and torture by Russian troops in the Ukrainian city Bucha in April 2022, as well as the deaths of relatives and friends fighting in the war were what motivated Alex Ryzhuk to leave Dublin and travel to the frontlines early in 2023.
"At that moment, I knew that, like, I can't... can't stay in Ireland anymore," he told Finn Boylan of FinnHouse Films.
"I have a few friends, guys from 18 to 23 that lost their life in this war, and a few older family members that also, unfortunately, lost their life in this war," he added.
When Alex spoke to Finn Boylan, he had been in Ukraine for just over a year. He was barely 18 years old when he left for the frontline. Prior to that, he had lived his entire life alongside his parents in Ireland.
"My parents, they're originally from Ukraine, from Rivne. They came over to Ireland over 23 years ago. I've been living in Ireland ever since," Mr Ryzhuk said.
Before he went missing, Alex, who was a drone pilot with the Ukrainian 3rd Separate Assault Brigade, operating under the callsign 'Irlandets,' had spoken about his intention to return to Ireland after the war.
"At the end of the day, I was born and raised in Ireland. Ireland has given me many opportunities and many things in my life that I'm grateful for. So, I would consider myself Irish, but at the same time, I cannot forget about my heritage and where my parents come from," he said.
"I went to school in Synge Street CBS [in Dublin 8]. It’s a pretty good school. I have lots of good memories from there. I'll have to come back to visit once I come back," he added.
He also said in the interview that he intended to return to Ireland and join the Defence Forces after the war in Ukraine concluded.
When Alex spoke to Finn about his involvement in the war, he spoke openly about his awareness of the dangers he faced on a daily basis.
"War is not a joke, death in war is a very high probability," he said. "It is something that constantly happens, even if it's not to you, it's to someone else, or to someone you know," he said.
"Some of the closest people you'll meet in your life happen to be at war. But unfortunately, you see many of your good friends gone also.
"War is brutal. If someone dies, the biggest responsibility we have at that point is to get their bodies back so they can have a proper funeral," he added.
WATCH: Irish film maker Finn Boylan on the frontline in Ukraine
In recent months he had fought in Avdiivka in some of the fiercest fighting over the last year of war, as well as in other areas along the frontline in Ukraine's east and south-east.
It is believed he went missing in the Kharkiv region.
"When someone dies for this cause, it's a person giving the most of what they have in their life," he told Mr Boylan.
"At the end of the day, the most valuable thing you have as a human being is your life. And those people who died unfortunately gave that for this country."
A spokesperson for the Department of Foreign Affairs said: "The Department of Foreign Affairs is aware of the case and is providing consular assistance. As with all consular cases, the Department does not comment on the details of individual cases."
An interview with Alex Ryzhuk is broadcast on 22 August edition of Prime Time on RTÉ One and RTÉ Player.
