Mullingar gardai are appealing for any witnesses following a two-vehicle collision at Ballinafid on the Longford side of the N4 overnight.
A man and a woman, the drivers of both vehicles, are understood to have been taken to hospital with serious but non-life-threatening injuries after the collision which happened about half-past three this morning.
Gardaí are asking anyone who may have been driving on the road around that time last night, or who might have dash cam footage to make contact with them at Mullingar garda station.
The road was closed for several hours as a result of the collision and there were significant traffic delays during rush hour traffic this morning.