More than 260 drivers have been caught speeding in the last 24 hours, with one motorist caught travelling at 163km/h in a 100km/h zone on the N11 at Newtownmountkennedy in Wicklow.
Another motorist was caught driving at 118km/h in an 80km/h zone on the N2 at Drumcaw in Co Monaghan.
In an update on its bank holiday roads policing operation, gardaí said that during the last 24 hours 264 drivers were detected speeding.
Since Thursday morning, 100 drivers have been arrested for driving under the influence of drugs or alcohol. That is more than one person arrested per hour, according to garda figures.
The roads safety operation began at 7pm on Thursday and will last until 7am on Tuesday.
The latest garda figures for speeding means more than 840 people have been caught speeding over the last three days.
Gardaí said they will be conducting both statutory mandatory intoxicant testing and high-visibility checkpoints during the operation.
They are appealing to motorists to use roads with care.
Gardaí added the highest risk of injury is between midday and 3pm each day during the long weekend.
Fourteen people have died on roads in the Republic and five other people were killed on roads in Northern Ireland so far this year.
