The Fox News cameraman killed in Ukraine after his car was struck with fire on Monday attended a secondary school in south Dublin.
Irish citizen Pierre Zakrzewski was killed along with local journalist Oleksandra Kuvshynova on the outskirts of Kyiv.
Reporter Benjamin Hall was also injured in the attack and is receiving treatment in hospital.
Read more: Taoiseach 'deeply disturbed' at death of Irish Fox News cameraman Pierre Zakrzewski in Ukraine
St Conleths College in Ballsbridge confirmed that Mr Zakrzewski was a past pupil of the school who graduated in 1984.
They paid tribute to him on Twitter, saying: "It is great sadness that St. Conleth's College acknolwledges the tragic passing of Past Pupil Pierre Zakrzewski (Class of 1984) in the Ukraine.
"Our thoughts and prayers are with his family and friends."
Taoiseach Micheal Martin confirmed this afternoon that Mr Zakrzewski was an Irish citizen.
He said on Twitter: "Deeply disturbed and saddened by the killing of Irish citizen and journalist Pierre Zakrzewski and one of his colleagues today.
"My thoughts are with their families, friends and fellow journalists. We condemn this indiscriminate and immoral war by Russia on #Ukraine."
In a tweet Fox News anchor John Roberts said it was "horrible news to report."
Read more: Ukraine war: Dubliner makes 5,000km round trip to Poland with van full of supplies for refugees
Read more: Ukrainian refugees in Dublin correct Sky News journalist over 'British' comment
"I worked with Pierre many times around the world," he added.
"He was an absolute treasure. Sending our most heartfelt prayers to Pierre’s wife and family."
Fox News chief executive Suzanne Scott tweeted: "It is with great sadness and a heavy heart that we share the news this morning regarding our beloved cameraman Pierre Zakrzewski. Pierre was killed in Horenka, outside of Kyiv, Ukraine."
"Pierre was with Benjamin Hall yesterday news gathering when their vehicle was struck by incoming fire. Pierre was a war zone photographer who covered nearly every international story for FOX News from Iraq to Afghanistan to Syria during his long tenure with us."
"His passion and talent as a journalist were unmatched. Based in London, Pierre had been working in Ukraine since February."
Read more: Fingal councillors call for rapid build homes to house refugees fleeing war in Ukraine
Read more: Ukraine war: Dublin donation drive needs baby food and toiletries
Sign up to the Dublin Live Newsletter to get all the latest Dublin news straight to your inbox.
