People have been killed and injured in an attack at a festival in the city of Solingen in western Germany, the German news agency dpa has reported. It was not immediately clear how many casualties there were. The report cited unidentified police sources as saying the weapon was believed to be a knife. No one has been arrested. The festival marking the city’s 650th anniversary began on Friday and was supposed to run through Sunday. The local Solinger Tageblatt newspaper reported that authorities called on people to leave downtown Solingen and that one of the festival organisers, Philipp Müller, said on a stage that emergency workers were fighting for the lives of nine people. Solingen has about 160,000 inhabitants and is located near the bigger cities of Cologne and Düsseldorf.