The young man who died following a collision with a LUAS tram in Dublin has been named as Cormac Ó Braonáin.
He was from the Windy Arbour area of Dundrum in south Dublin.
The 19-year-old had recently been elected as Chair of Labour Youth.
President Michael D Higgins paid tribute to "Cormac's energy, idealism, generosity, creativity and commitment to social justice and his vision of a kinder, more just society were exemplary. He will be dearly missed by all who knew him.
"Sabina and I express our deepest condolences to his family and friends and to all those who were privileged to know him."
Labour Party Leader Brendan Howlin said that Cormac "had taken up the position with energy, enthusiasm and passion", adding that he had made "a huge impression, working tirelessly to advocate for the politics of our movement".
"When someone so young dies it is hard to find the words to express our loss but in his short time with us, he leaves a strong legacy," said Mr Howlin.
A two-hour vigil was held in his memory at Lios na nÓg in Ranelagh.
So sorry to learn of the tragic passing of Cormac Ó Braonáin, Chairperson of Labour Youth and SDLP member. Thinking of his family and friends today.— Colum Eastwood (@columeastwood) December 15, 2019
Cormac was pronounced dead at the scene after he was struck by a LUAS tram shortly after 3am at Peters Place near Charlemont Bridge on the southside of the city.
The Luas Green Line was later reopened.
The tram was operating as part of the special late night pre-Christmas service.