Austrian police say a former Nazi concentration camp has been vandalized with anti-Muslim graffiti. Police in Upper Austria province say the graffiti extends about 20 meters (66 feet) along the outer wall of the former Mauthausen concentration camp, which is now a memorial site. Police said Friday the crime occurred overnight, either late Wednesday or early Thursday. An investigation is under way. The Nazis shot, gassed, beat or worked to death about half the 200,000 inmates in Mauthausen’s main camp or its affiliates. It got its name from the nearby town of Mauthausen, about 155 kilometers (96 miles) west of Vienna.