Throughout yesterday wreaths and bunches of flowers were placed at the tree in Clondalkin where the 15-year-old boy lost his life.
He had been a passenger in a car which mounted the kerb and smashed into the tree at Station Road at 10pm on Saturday.
The other four boys in the car, all aged between 14-16, suffered non-life threatening injuries, though one had to be taken to Our Lady’s hospital for sick children in Crumlin in a serious condition.
The car had not been reported stolen and so part of their investigation is focusing on how it came to be in the boys’ possession.
Superintendent Dermot Mann said they were appealing for anybody who may have seen the red Kia Magentis car, 02 KE 10872, travelling anywhere from the Cherry Orchard, Ballyfermot area towards Clondalkin at or around 10pm.
Witnesses to the crash or anyone with information have been asked to contact Ronanstown Garda Station on 01 666 7700.
Meanwhile, a motorcyclist died in North Cork yesterday afternoon after he collided with a car.
The accident happened at Scartbarry in Watergrasshill at approximately 1pm.
The 55-year-old victim was pronounced dead at the scene.
His body was taken to Cork University Hospital where a postmortem will be carried out this morning.
The female driver of the car and her 11-year-old male passenger were not injured.
Gardaí closed off the road for a number of hours while a forensic examination was carried out.