A technical examination is due to be carried out on a stretch of road between Laghey and Ballintra following a serious crash yesterday afternoon.
Gardai say that the road is expected to stay closed until later this afternoon.
Gardaí and emergency services attended the scene of the two vehicle collision which occurred at Coxtown near Laghey.
The collision between a lorry and a car occurred shortly after 4pm.
The driver of the car a woman in her 40s and the front seat passenger, a male teenager, were taken to Sligo University Hospital where they are continuing to receive treatment for serious injuries.
Gardai are appealing to anybody who may have witnessed the collision or who may have been travelling on that stretch of road between 3.45pm and 4.15pm and had a dashcam to make contact with Gardaí in Ballyshannon on 071-9858530.
