The N5 reopened to traffic outside Castlebar at approximately 6pm yesterday evening following a serious collision between a lorry and a car.
Gardaí and emergency services attended the scene of the incident, which occurred at around 10am in the morning on Saturday near Windsor.
Midwest News understands that there was one occupant in each vehicle.
One of the individuals was dealt with at scene, while the other, a man in his 70’s, was taken by ambulance to Mayo General Hospital with serious injuries.
The road reopened after several hours yesterday so a technical examination of the scene could take place.
Gardaí say investigations into the incident are ongoing and are urging anybody who was in the area at 10am yesterday morning that may have seen the incident or who has dashcam footage to contact Castlebar Garda Station on 094 903 8200.