In September of 1935, authorities in Berlin were plagued by a sudden rash of unexplained -- and unsolved -- violent crimes. While firemen were kept busy with an outbreak of arson accidents, blamed on "malignant maniacs," other culprits were stretching taut wires across rural highways by night, wrecking cars and injuring or killing their occupants. Robbery was suspected as a motive in one or two of the incidents, but for the most part, victims were not molested after their vehicles crashed. According to the local press, "The similarity of the method of fastening the wires leads the police to believe a maniac is the chief culprit." Without motives or suspects, investigators could do little but stand by and watch as the body-count escalated. Local auto dealers were more resourceful, cashing in on the panic while it lasted by offering their customers saw-toothed guards for the front of their cars, designed to clip cables on impact.