Guernsey Police are warning islanders about cables and boulders being left on unlit roads.
The hazards have been appearing in the area of La Vrangue and Maurepas Road in St Peter Port.
Officers are working to find who is responsible and are asking people driving in the area to be vigilant.
For anyone foolish enough to think this is a funny prank to do, it is not. Actions like this could lead to very serious consequences for the offender and could cause a tragic collision.