The emergency services have been dispatched to the scene of a road traffic collision on the Glenshane Pass.
"Police are dealing with a road traffic collision at the bottom of the Glenshane Pass," the P.S.N.I.
Initial assessments of the incident suggest no one was seriously injured but the P.S.N.I. is advising motorists to avoid the area.
"We do not believe anyone is seriously injured at this stage but traffic is down to one lane with lengthy tail backs at this stage.
"Please avoid the area at this stage."