BERLIN – Eighteen people were injured in a knife attack in Hamburg station on Friday evening, Germany's Bild newspaper reported, and local police confirmed they had arrested the suspected assailant.

Four victims are in critical condition and six others are seriously injured, Bild reported, saying the motive for the attack was unclear.

Police said the suspected assailant was a 39-year-old woman who allowed herself to be arrested without resistance.

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"So far we have no evidence that the woman could have acted with political motivation," said Hamburg police spokesperson Florian Abbenseth.

"Rather, we have findings on the basis of which we are now investigating in particular whether she may have been in a state of mental distress."

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German Chancellor Friedrich Merz wrote on social media platform X, formerly called Twitter, that the news from Hamburg was "shocking."

"My thoughts are with the victims and their families," he said.