One person has been seriously injured in a two-vehicle collision on the main Letterkenny to Derry road.
Gardai say the crash between a tractor and a car happened shortly before 5.30 this evening.
The driver of the car is understood to be seriously injured while the condition of the person driving the tractor is unknown at this stage.
The road near Burt is closed at this time and motorists have been advised to seek alternative routes.
People travelling from Letterkenny to Buncrana have been asked to travel via Newtowncunningham and Killea onto Bridgend.