Investigations are underway into an arson attack on three derelict buildings in Donemana.
Emergency services battled the blaze which broke out shortly after 5am this morning on Longland Road.
Northern Ireland Fire and Rescue Service believe the fire was started deliberately.
Police are appealing to witnesses who may have noticed any suspicious activity in the area this morning around or shortly after 5am, or anyone with information to contact them on 101.