An investigation has been launched after tag readers were damaged on the M50 yesterday.
Overhead cables on the Northbound toll bridge were cut and forced the motorway to be shut down for an hour.
Motorists were able to use the road "toll free" for a period of time and the incident is said to be worth about €100 euro to the exchequer.
Gardaí at Blanchardstown say the incident occurred at the gantry of the eflow barrier at around half 9 last night.
A 48 year old man was arrested and taken to Blanchardstown Garda Station and detained under the provisions of Section 4 – Criminal Justice Act .
The toll company e-flow could not be contacted for comment.