Gardaí investigating a fatal knife attack in Dublin at the weekend have arrested a fourth person today.
The teenage boy was picked up by officers yesterday evening.
He is currently being held at Pearse Street Garda Station under Section 30 Offences Against the State Act 1939.
Three other people arrested in relation to the investigation - a woman in her 40s and two teenage boys - were released without charge this morning.
A 22-year-old German man died in the attack at an apartment block in Rialto in the early hours of Saturday morning, while a second man was also injured in the incident.