The Irish deputy premier Micheal Martin has expressed sympathies to the family of an Irishman killed in Ukraine.
Finbar Cafferkey, from Achill Island, Co Mayo, is reported to have been a military volunteer in the eastern part of the country.
He was reported to have been killed near Bakhmut.
Mr Martin said: “My deepest sympathies to the Cafferkey family on the sad passing of Finbar.
“He obviously was a young man of clear principles.
“Our thoughts and our prayers are with the family today.
“I think the family have asked for privacy, I’m not going to comment any further on it at this particular time. I’ll allow the family space to grieve what is a very, very sad loss for them.”
Mr Cafferkey had previous combat experience in the Syrian conflict.
He had travelled to Syria to volunteer with the YPG in their fight against Isis in Rojava.
He has been described in online tributes as a “respected activist”.
Prior to the Syrian conflict, Mr Cafferkey was involved in the Shell to Sea campaign which is opposed to the construction of a natural gas pipeline in the west of Ireland.
A statement on the group’s website said: “We are all heartbroken to hear of the death of our brave friend Finbar, who was guided by the principles of freedom and equality for all.
“Heartfelt sympathies to all his family and friends. Rest in peace.”
He had participated in rallies with the group.
Mr Cafferkey’s activism on environmental issues, homelessness and migration has also been praised in tributes.