Two young men have been killed in a crash on the A5 Victoria Road between Newbuildings and Magheramason. Two others are in hospital.
The one vehicle crash happened at around 3.30 this morning between Duncastle Road and Woodend Road.
Diversions are in place, and motorists are advised to avoid the area.
The PSNI are appealing for information about the movements of a black Volkswagon car travelling from the Strabane direction.