Irishman, Rory Mason, has been killed while fighting in the Ukrainian war.

Mason, 23, died while fighting in the International Legion for the Defence of Ukraine as part of the Ukrainian Armed Forces. The young man was located in the Kharkiv region when he passed away on Wednesday, September 28, the Irish Examiner reports.

Rory's family are been devastated by the loss, with his heartbroken father, Rob, saying how proud he was of his son's "courage" and "selflessness."

"Rory was a private young man of drive, purpose and conviction. Though we are deeply saddened at his death, we are enormously proud of his courage and determination and his selflessness in immediately enlisting to support Ukraine," the grieving father said.

"Rory was never political but he had a deep sense of right and wrong and an inability to turn the other way in the face of injustice. He had a long-standing interest in Eastern Europe, in travel and in learning new languages, including Russian."

Rory is deeply missed by his whole family, his parents Rob and Elizabeth, and his younger brother and sister.

The top priority for the Mason family following Rory's death is to repatriate the fallen soldier's remains.

"Those who fought alongside Rory speak of ‘a truly brave and courageous man who could have left at any time but chose not to’," Rob added. "In the words of a colleague who served with him, ‘Rory was a man who from a glance could seem shy however when it came to actions and character he proved, again and again, he was a man of fortitude, principal and honour’."

Finally, the family appealed for privacy: "Rory was our son and we will miss him enormously. As our family is still trying to come to terms with Rory’s death, we would appeal for privacy at this difficult time."

A statement from the International Legion for the Defence of Ukraine said: "Our brother in arms, Rory Mason has taken part in the Kharkiv counteroffensive with his unit and was killed in action. While conducting operations, the unit came under attack.

"We are in contact with the family and in coordination with them, following their wishes and instructions, the International Legion and the Armed Forces of Ukraine are handling the repatriation process. At this time, to protect operational security and the family’s privacy we cannot release more information."

The war in Ukraine started in February this year after Russia invaded the country. The number of civilian deaths so far has been estimated at nearly 6,000, with around 10,000 to 11,000 Ukrainian soldiers have killed in the conflict.