Gardaí in Dún Laoghaire have made issued a fresh appeal for information on the 1999 murder of Raonaid Murray today.
Today is the fourth anniversary of the 17-year-old Dubliner's death.
Ms Murray was fatally stabbed in an attack near her home at Silchester Park, Glenageary, at about 12.10 a.m. on Saturday September 4th, 1999.
Insp Eamonn O'Reilly of Dún Laoghaire Garda station said he remains hopeful of a breakthrough.
"We have interviewed 9,000 people, taken 3,500 statements and arrested 14 people. Some of those arrested have been eliminated from our inquiries, but others, for one reason or another, haven't. So we are hoping somebody can provide us with something, however small they might think it is."
A reward of €190,000 has been set for anyone with information leading to conviction.
Gardaí are anxious to talk to anybody who can say where Raonaid was from 11.20 p.m. when she left Scott's Public House, Dún Laoghaire, to 12.30 a.m. when her body was found. Dún Laoghaire gardaí can be contacted at 01-6665000.