Taoiseach, Tánaiste and Minister for Education describe tragedy as "heart-breaking".
Tributes are being paid to the young people who died when a car overturned in Clonmel yesterday evening.
Three teenage girls were killed along with a man aged in his 20's.
It is understood the girls received their Leaving Cert results yesterday.
The single car crash happened at around 7.30 pm.
The victims have been removed from the scene and taken to hospital, and post mortem examinations will take place in the coming days.
Gardai have warned video footage and images of the immediate aftermath of this incident are being shared on social media and say they are aware of the presence of a private drone over the collision scene.
They are urging the public not to share this footage.
They are also appealing to anyone with information to come forward.
The Taoiseach, Tánaiste and Minister for Education have all described the tragedy as "heart-breaking".
The Taoiseach has described the deaths of the four young people as "truly devastating and heartbreaking", while Tánaiste Micheál Martin has said he is "deeply saddened" by the tragic loss of life.
Education Minister Norma Foley says Department, through the National Educational Psychological Service will provide essential supports to staff and students.

Gaelic Players Survey Reveals Drug Misuse Numbers
452 Incidents Reported In Naas General Hospital In Last Three Years
Over 600 Fewer Frontline Gardaí As Staffing Figures Release
Nationwide Fuel Protest Set To Take Place Tommorrow
Woman Dies In Crash As Over 3,000 Drivers Caught Speeding During Bank Holiday Weekend
Calls for Increased Traffic Garda Presence Ahead of Bank Holiday Weekend
Over €2,000 Damage Caused in Vandalism at Athy Sports Ground