Additional reporting by Vivienne Clarke.
A member of Óglaigh na hÉireann, the Irish Defence Forces, was killed while carrying out UN peacekeeping duties in Lebanon on Wednesday night.
Private Seán Rooney (23), from Newtowncunningham, Co Donegal, was involved in a "serious incident" at approximately 9.15pm Irish time, when two-vehicle convoy carrying members of the 121st Infantry Battalion — United Nations Interim Force In Lebanon, or UNIFIL — came under "small arms fire" in al-Aqbieh, southern Lebanon.
Private Rooney joined Óglaigh na hÉireann in March 2019. He previously served overseas with the 119th Infantry Battalion UNIFIL.
Following the incident, Private Rooney, along with three other soldiers, were brought to a hospital near Sidon. The young peacekeeper was pronounced dead on arrival.
Another soldier, named as Private Shane Kearney (22), remains in a "serious condition" having undergone surgery.
Private Kearney, from Killeagh, Co Cork, joined the Defence Forces in October 2018.
Two other soldiers were being treated for minor injuries.
Minister for Defence Simon Coveney described the incident as shocking and tragic.
It was the first fatality in 20 years for the peacekeeping force, he told RTÉ radio’s Morning Ireland.
Since 1978, Ireland has participated in 30,000 tours of duty in Lebanon, where good relationships have been established with locals, Mr Coveney added.
“This was not expected, yes there were some tensions on the ground, but nothing like this.”
Mr Coveney explained the Irish personnel were travelling to Beirut in two armoured vehicles on a standard run.
It was uncertain what had happened, but the two vehicles became separated and one was surrounded by “a hostile mob”. Shots were fired and one peacekeeper was killed and another seriously injured and two others suffered less serious injuries but remain in hospital.
A senior Hezbollah official described the attack as an "unintentional incident" on Thursday, stating the armed group was not involved.
Wafiq Safa told Reuters his party offered its condolences "after the unintentional incident that took place between the residents of al-Aqbieh and individuals from the Irish unit," and urged the party not be "inserted" into the incident.
The families of the deceased and injured soldiers were informed of the incident between 2am and 5am on Thursday.
Mr Coveney said it was not news that any family wanted to hear, but the decision was taken to make the visits in the early hours of the morning ahead of social media posts.
When asked about clips which were already being shared online, the Minister said he did not know what had been verified, so it was important that a full and proper investigation be carried out.
"It is with deep regret that Óglaigh na hÉireann can confirm the death of one of our peacekeepers in a serious incident in Lebanon last night," the army said in a brief statement, published on Twitter.
A full investigation will be carried out into the incident, the army said.
It is with deep regret that Óglaigh na hÉireann can confirm the death of one of our peacekeepers in a serious incident in Lebanon last night.
Ar dheis Dé go raibh a anam dílis.
— Óglaigh na hÉireann (@defenceforces) December 15, 2022
In a statement, President Michael D. Higgins said it was with "deep sorrow" that he learned of the news.
"As a people, we take great pride in our unbroken record of peacekeeping with the United Nations. However, we must never forget the dangers that come with this work, or how the members of our Defence Forces serving on peacekeeping missions abroad risk their lives every day in order to build and maintain peace in conflict zones across the world.
"As President of Ireland and Supreme Commander of the Defence Forces, it is with a heavy heart, and conscious of the great loss it will represent to them, that I offer my deepest condolences to the family, colleagues and friends of the member of the Defence Forces who has lost their life. A life lost serving the people of Ireland, serving the United Nations, and serving all those wishing for peace in our shared world.
"May I also wish a speedy recovery to those other members of the Defence Forces injured in the incident. Our thoughts are with them at this time," he said.
Taoiseach Micheál Martin expressed "heartfelt sorrow" following the loss of "a young person serving overseas".