A guard has been arrested on suspicion of drink-driving and has been suspended from duty.
Gardai in Navan in Co Meath attended the scene of a single vehicle collision involving an unmarked official Garda car with one occupant on the M3 at 10.30am yesterday.
The driver - a member of An Garda Síochána - was arrested at the scene on suspicion of driving under the influence of an intoxicant.
A criminal investigation into breaches of the road traffic act is currently ongoing.
An internal disciplinary investigation has also begun, and the guard has been suspended from duty.