Gardai confirmed they are quizzing arrivals into Dublin Airport at checkpoints surrounding the area.
Currently no non-essential travel is permitted in or out of the country, while arrivals now have to produce a negative PCR test when coming into Ireland.
And Gardai are set up around the airport stopping cars on the way to and from the terminals.
A spokesperson said: "Checkpoints have been taking place in the vicinity of Dublin Airport as part of ongoing operations surrounding non-essential travel including international travel in support of public health measures to reduce the spread of Covid-19."
They added: "Various checks on Public Health Regulations at ports/airports. FPN can be issued for non essential travel, includes non essential international travel.
"Arriving international travellers must present negative PCR test, failure can be prosecuted in District Court max €2500 fine."
Mandatory quarantine for arrivals into Ireland is currently being discussed although Tanaiste Leo Varadkar said during the week it is unlikely to happen with the North potentially being used as a backdoor.
However, NPHET have said they are in favour of introducing the rule so that non-essential travel can be limited.
Dr Ronan Glynn, Deputy Chief Medical Officer, told the Oireachtas this week: “Our advice is there, it’s published. We previously asked for mandatory quarantines and recently we asked for an added element of discretion as it applies to travel to be removed, insofar as is possible.
“What we want is a situation where non-essential travel is reduced to the greatest extent possible.”
