The mayor of the Polish city of Gdansk died in the hospital when he was stabbed to a charity event.
Pawel Adamowicz, 53, was attacked on Sunday in front of hundreds of people on stage.
He was hospitalized and operated on for serious abdominal injuries.
A 27-year-old, who has a criminal record, was arrested for the attack.
Poland's Health Minister confirmed on Monday that Adamowicz had died of his injuries.
"We could not win," Lukasz Szumowski told the local media.
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