Gardaí have renewed their appeal for information about the unsolved murder of Raonaid Murray.
Ms Murray was viciously knifed near her home in Glenageary, Co Dublin three years ago.
Gardaí have been unable to find her killer despite interviewing 9,000 people and taking more than 3,000 statements.
The 17-year-old was repeatedly stabbed with a large, broad-bladed knife by her attacker, who was possibly lying in wait as she walked home from a pub.
She staggered about 100 yards towards her home after the attack before collapsing, where she was discovered by her sister Sarah and two of her friends who had just arrived in a taxi.
At the time, Assistant Garda Commissioner Jim McHugh described the murder as "a motiveless, very savage, vicious attack", and added: "It is an investigation that we must solve and one we will solve."
But today, on the third anniversary of her death, Gardaí still have not established a motive for the killing and despite several arrests, no one has been charged.
Gardaí have again appealed for anyone who saw the last movements of Ms Murray after she left Scott's pub in nearby Dun Laoghaire.
They are also appealing for anyone who gave her a lift between Dun Laoghaire and Glenageary or anyone who saw or heard a struggle in the street at around 12.10 a.m. on September 4th, 1999.
PA