Dublin airport reopened shortly after 4 o'clock this afternoon after passengers and workers were evacuated from the terminal for two hours because of a bomb scare.
Departure flights from the airport are expected to resume after 5pm. A spokesman said it was hoped the backlog of flights would be dealt with by 6pm.
However, traffic is reported to be extremely congested in the area.
A Garda spokeswoman said a man entered the airport terminal with a bag at about 1.45pm and indicated it contained a bomb.
The bag was retrieved and the man was detained. He is reported to be an Irish man in his fifties. He is being held in Santry Garda station under Section 30 of the Offences Against the State Act.
Gardaí declared the airport to be safe after the bag was examined by army bomb experts.
"It seems a man walked into the arrivals hall and said he had a device in a bag," a Defence Forces spokesman said. "Having x-rayed it and remotely opened the bag, the bomb squad found nothing but some old clothing and some newspapers," another spokesman said.
Approximately 9,000 passengers and 50 flights, arrivals and departures, were affected during the two-hour disruption. While all airlines are endeavouring to get back to normal, most flights are delayed by approx one to one and half hours.
Passengers who have concerns regarding their specific flight should contact their individual airline.
A spokeswoman for the airport added that all traffic was prevented from entering the airport grounds, and a number of roads were sealed off.
No flights were allowed to take off during the alert incident. Planes were able to land, but passengers were not allowed to disembark.