Almost 90 passengers missed their flights at Dublin airport this morning as a result of delays at airport security.
Aer Lingus said 35 of its passengers did not make their flights, while 50 Ryanair flyers missed theirs.
Ryanair said some passengers were waiting up to 45 minutes to pass through security.
It has called on the airport authorities to investigate reports that security staff are operating on 'a work to rule' basis.
However, SIPTU said this evening that industrial action involving airport security in any shape or form had not been sanctioned by the union.
Tonight, the Dublin Airport Authority said airport security was working at full capacity today and added it was unaware of any industrial action.
A spokeswoman also said that some passengers were not leaving the necessary time for checking in.
