A man has been injured after he came off his bike near Ballindrait in Lifford this morning.
The incident happened just after 9pm on the Springhill Road.
The man was rushed to hospital and is understood to have sustained serious head injuries.
It is understood the man was in collision with a vehicle.
Garda forensic investigators have closed the road for an investigation and it is believed the road will remain closed for the rest of the morning.