The Glenshane Road in Derry is been closed following a serious road traffic collision.
Police say the crash happened at 4.25pm this afternoon.
The road was closed earlier also following an early morning fatal collision.
Diversions are in place for Belfast bound traffic at the Glenshane Road junction with the Tirbracken Road while Derry bound traffic is being diverted at the Foreglen Road junction with Baranailt Road.
Motorists are advised to seek alternative routes.