BERLIN (AP) — People were killed and injured in an attack on Friday at a festival in the city of Solingen in western Germany, the news agency dpa reported. It wasn’t immediately clear how many casualties there were.

The local Solinger Tageblatt newspaper reported that authorities called on people to leave downtown Solingen and that one of the festival organizers, Philipp Müller, said on a stage that emergency workers were fighting for the lives of nine people.

The dpa report cited unidentified police sources as saying the weapon was believed to be a knife and no one had yet been arrested. The attack happened on a central square, the Fronhof.

The “Festival of Diversity,” marking the city’s 650th anniversary, began on Friday and was supposed to run through Sunday, with several stages in central streets offering attractions such as live music, cabaret and acrobatics.

Solingen has about 160,000 residents and is located near the bigger cities of Cologne and Duesseldorf.