Five people in their 20s died in a road crash in Co Louth on Saturday night.
Irish police said three others were injured in the two-vehicle crash, which they have described as “shocking and devastating”.
Ireland’s deputy premier Simon Harris said a “veil of deep sadness” had come over the country.
An investigation has begun into the accident on the L3168 at Gibstown, just outside Dundalk.
Speaking near the scene on Sunday, Superintendent Charlie Armstrong said: “Yesterday evening, just after 9pm, there was a serious road traffic collision involving two vehicles, a Volkswagen Golf and a Toyota Landcruiser.
“Five occupants of the Volkswagen Golf, three males and two females, all in their early 20s, are deceased at the scene.”
Mr Armstrong said a man in his 20s in the Volkswagen and a man and woman from the other vehicle were taken to Our Lady of Lourdes Hospital, Drogheda, for treatment.
He said family liaison officers have been appointed to each of the families and gardai will keep them updated.
Mr Armstrong said: “I want to express my condolences and sympathies and the sympathies of every member of An Garda Siochana to the families of the five young adults who lost their lives yesterday evening in this road traffic collision.
“Last night members of An Garda Siochana, supported by other emergency services including Dundalk Fire Brigade, HSE paramedics and staff at Our Lady of Lourdes Hospital, Drogheda, initiated a major incident response.
“The scene here on the L3168, Gibstown, remains closed today and a technical and forensic examination is being carried out by An Garda Siochana forensic collision investigators.”
He said post-mortem examinations would be carried out.
Mr Armstrong added: “I want to acknowledge and express my gratitude to my colleagues in An Garda Siochana and the other emergency services who attended the scene last night.
“The scene was very difficult, in adverse weather conditions, and the professionalism shown by all first responders and the care and respect shown to the five deceased was exemplary.
“This tragedy, with the loss of five young adults will have a deep impact on families and local communities in Carrickmacross, Dromconrath and in Scotland.
“This is a shocking, devastating event for these families, their communities and the community here in Dundalk.
“I want to take the opportunity to appeal to any person with any information on this road traffic collision to contact the investigation team at Dundalk Garda Station.
“I am appealing to any person who was on the L3168 between 8.30pm and 9.15pm, last night Saturday November 15 2025, to contact the Garda investigation team.
“I am appealing to any person who might have any camera footage or images from the L3168, Gibstown area, between 8.30pm and 9.15pm last night, to give that footage or images to the investigation team at Dundalk Garda Station.
“The investigation team can be contacted at Dundalk Garda station on 042 9388400, the Garda confidential line on 1800 666 111, or any Garda station.”
He added: “Finally, I once again want to express my sympathies to the families of the five young people who lost their lives yesterday evening.”
Tanaiste Mr Harris said: “A veil of deep sadness and shock has come over our country this morning with the news emerging of the devastating loss of five young lives overnight in a road traffic accident in County Louth.
“This morning, my thoughts, and I know the thoughts of people right across our country, are with the families of those who have lost loved ones, their friends, and their communities.
“We keep them in our prayers and in our thoughts now and in the time ahead.
“I also want to pay tribute to the emergency services.
“One cannot even imagine the extraordinarily difficult and tragic circumstances in which they found themselves working last night as they set about trying to help in the most harrowing of situations.”
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