From International Business Times:

A few hundred Kurdish protesters then gathered at a mosque near the train station before they were attacked by a group of 40 armed supporters of IS. Four people were taken to hospital with stab wounds following the incident.

Police used water cannons, batons and pepper spray to bring the unrest under control while both sides threw stones and bottles in an attempt to break police lines and attack the other.

The clashes in Celle occurred a day earlier, with 100 Kurds and 100 Muslims brawling until police calmed the situation.