They later said that they could not rule out that more people were injured in the attack. German news agency dpa said the revellers were football fans from a local team who defended themselves against the attacker before he fled. The city’s Arminia Bielefeld soccer club won its match on Saturday, and with it became third division champions. According to the police, the attacker was probably also injured in the face. Bielefeld police said they found several knives at the scene and that they have activated a witness hotline asking people to upload videos and photos of the attack. They said anyone who sees the man should to keep a distance and call emergency services as he may be armed and dangerous.