"A joke", "shambles", "mental" and "shameful" were just some of the words used by Dublin Airport passengers to describe the scenes on Sunday morning.
People took to social media in their droves to share their outrage and frustration at the queues which stretched far outside the terminal buildings.
Tearful scenes were reported after people missed flights, while others claimed there were angry scuffles as some became volatile in the queues.
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Many people waited 2.5 hours or more to get through the lines outside and inside to security, with some experiencing even bigger delays.
One man got through security four hours after arriving in the Dublin Airport car park, while another who arrived five hours before their flight was "sceptical" they would make it.
In a statement, a spokesperson for Dublin Airport said: "Dublin Airport is experiencing significant queues for airline check-in, bag drop and security screening this morning as 50,000 passengers are expected to depart over the course of the day.
"Queuing outside both terminals has been deployed since early morning as part of Dublin Airport’s contingency plans for the increased numbers of passengers travelling.
"Due to significant queues inside the terminals passengers queueing outside the terminal have been advised they may not make their flight and may need to contact their airline to rebook. Dublin Airport sincerely apologises for the obvious frustration and inconvenience this is causing."
It comes after Dublin Airport had pledged that passengers will get through security in 30 minutes or less from early June, with the DAA’s head of communications saying on Saturday that airport bosses are days away from fixing some of the main problems causing delays.
Passengers flying from Terminal 1 and 2 on Sunday posted images and videos online of the scenes, with many sharing their experiences, the Irish Mirror reported.
One person said: "Dropped my daughter off 7.40am this morning. Still queueing outside airport at 10am. Fight broke out as people pushed in. No airport staff anywhere. Doors closed. Bedlam."
A second said: "Situation at #DublinAirport today beggars belief. Lifts and stairwells closed to prevent passengers getting to security. Queues so long that they are wrapping the entire way from first floor, down escalators and around the ground floor of the building - mental!"
A third said: "#DublinAirport a joke this morning. My daughter queuing for 2.5 hours and still not inside the terminal 1 building ….Little or no queue management."
A fourth wrote: "4hrs after arriving at the carpark we're finally through security. Missed the flight of course. Ryanair have us on standby for a flight this afternoon."
A fifth commented: "Around 800 people outside waiting to get in and when I got in there was no joke around 3K people inside. Got to the boarding pass scanner and was told they couldn’t let anyone else in yet and missed my flight #DublinAirport #joke."
A sixth said: "Miles long queue at @DublinAirport. Here 5 hours before my flight and still sceptical if I will make it or not! #AirportTwitter #DublinAirport."
A seventh wrote: "2.5hour queue just to get inside #DublinAirport #crazy."
Someone else said: "10am had to go back@to collect people who missed flight .. shambles - system has collapsed #DublinAirport #daa."
Another added: "There I am in that chaotic queue, been here since 8.45am and I’m still outside, very unlikely to make my flight and I’ve literally seen 2 staff trying to make sense of this. It’s still May what on earth will it be like in summer, so disgraceful."
While one passenger stated: "What the actual f**k @DublinAirport ????? In what world is this ok?? Queuing for 30 minutes already and at the very least another 30 to go. Then at least an hour inside??? Shame on you!"
Another said: "@DublinAirport people are arriving to boarding gates and breaking down in tears either because they have missed their flight or from the relief of just making it. It’s shocking stuff.#DublinAirport"
And this person commented: "#DublinAirport this is crazy. @DublinAirport you should implement a triage based on the time of the flights! We are risking losing our international flight! You advise us not to arrive too early, not to arrive too late. Which recommendation should be considered?"
As of 11am on Sunday, the wait time according to the Dublin Airport website was 50 minutes for Terminal 1 and 40 minutes for Terminal 2.
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