Specialist Garda units have carried out a simulated anti-terror operation in central Dublin.
The exercise involved attackers targeting people at the Docklands railway station before taking hostages on a train.
The operation was partly designed to measure response times for elite Garda units and involved officers reacting to victims of knife attacks and confronting armed terrorists.
Justice Minister Charlie Flanagan said he hoped the exercise would give the public reassurance.
"While a terrorist attack here may be unlikely, the authorities are in no way complacent in the measures being taken to respond to that threat," he said.
"The exercise today is part of an ongoing process of planning and training that, to a large extent, takes place quietly and behind the scenes. That said, this work goes on relentlessly."
The exercise began with a simulated report of a car crash at Spencer Dock to which local units were dispatched.
The scene they were confronted with included an injured person on the ground and people having been stabbed.
The officers were also told of a report of two attackers - one armed with a gun and one a knife.
The exercise then moved inside the station.
