The Taoiseach has described last week's stabbing of a young man in a Dublin park as "really shocking" and called on anyone with information to contact the authorities.
Azzam Raguragui, an 18-year-old from the Dundrum area, was stabbed in Finsbury Park in Dundrum just after 8pm on Friday 10 May.
Yesterday, his family said that they have faith in the Irish justice system to hold the perpetrators to account.
His killing was raised in the Dáil by Labour Party leader Brendan Howlin, who said knife crime was becoming more and more common.
Mr Howlin pointed to the rise of knife crime in the UK, and said the number of knives seized here in Ireland has risen by two thirds since 2016.
He said 264 knives were seized by gardaí in the first six weeks of this year alone.
"The family of Azzam are saying, I think very heroically, that they are resting their faith in the Irish justice to hold the perpetrators to account," Mr Howlin said.
Leo Varadkar said he wanted to join with all members in extending sympathy to the family.
"I heard his father say he has trust in our justice system, in our police and in our courts to ensure that the perpetrators are found and prosecuted and it is our job to ensure that trust is not misplaced," he said.
The Taoiseach also said he was aware of the debate in the UK about the rise of knife crime.
"I'm not quite sure if it is the case that knife crimes are as frequent here as they are in the UK, but they certainly are occurring and they should be of concern to all of us," he said.
Solidarity- PBP TD Richard Boyd-Barrett said his son socialised in the same area and would have see Azzam there regularly.
Mr Boyd-Barrett said that while knife crime is shocking, teenagers were not provided with more productive things to do.