Gardaí have appealed for witnesses after a 34-year-old man was critically injured when the van he was a passenger in overturned on the Drumkeen to Stranorlar road, in the town land of Ballinaglack, Stranorlar.
The single vehicle accident occurred on Saturday evening at approximately 20 minutes to 10.
Two other men travelling in the van were treated at the scene for minor injuries.
The injured man was taken by ambulance to Letterkenny Hospital.
Forensic collision investigators were at the scene on Sunday and the road was closed to traffic.
Anyone with information is asked to contact Letterkenny Garda Station 074 67100, Ballybofey Garda Station 074 9137740, or the Garda Confidential Line 1800 666 111.