German police say they have arrested a 15-year-old in connection with a knife attack in the western German city of Solingen, BBC reports.

Four more are "very seriously injured" in the attack, police say.

Police say a motive is still not clear but they say they cannot rule out a "terrorist" motive.

Local mayor Tim Kurzbach says those who were at the event are in a state of "shock, horror and great grief".

Meanwhile, German Chancellor Olaf Scholz says the suspect must be "punished to the full extent.

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