Gardaí have arrested three teenagers after a car they had been pursuing crashed into another vehicle on the N7 on Thursday afternoon.
Gardaí were following the car as part of anti-burglary initiative Operation Thor before the crash took place.
One person, a male in his teens, was seriously injured in the crash and was taken by ambulance to Tallaght Hospital.
A Garda spokesperson confirmed the matter had been referred to the Garda Síochána Ombudsman Commission (Gsoc).
Gardaí said the incident began at 3 pm when they received a report of a burglary at house in Athy. The intruders were disturbed and fled from the scene in a waiting car when the occupants of the house returned home.
During a follow up operation, members of the Garda anti-burglary unit intercepted a car on the N7 at approximately 3.45pm.
The car initially stopped for gardaí but when approached took off at speed in the direction of Dublin, gardaí said.
“Moments later this car was involved in a collision with a second car at on the N7 at junction 8, Johnstown,” they added.
While one occupant of the speeding car was taken to hospital with serious injuries, three other youths - all male and understood to be in their teens - were arrested during follow up searches near the crash site.
All three have been detained for questioning under section 4 of the Criminal Justice Act, 1984 at Naas Garda Station.
The driver and sole occupant of the second car was taken to Naas Hospital with minor injuries.
The scene of the collision was being examined on Thursday night and traffic diversions remained in place.
AA Roadwatch warned motorists to find alternative routes as theN7 was closed northbound between junctions seven and eight, the Johnstown and Kill junctions.
It said commuters were experiencing “heavy delays” following the incident.
There were also delays in both directions through Newbridge.
The Celbridge/Ardclough road will remain closed until further notice and motorists are advised to use an alternative route.
Gsoc appealed to anyone who witnessed the incident to contact it especially anyone who may have dash cam footage from the area. Anyone with information that could help its inquiries is asked to contact Gsoc on 1890 600 800.