Pwel Adamowicz, mayor of Gdansk in Poland, has died in hospital a day after he was stabbed at a charity event.
Adamowicz, 53, was attacked on stage while addressing hundreds of people on Sunday.
The mayor was attacked while attending the Great Orchestra of Christmas charity; an annual event where volunteers raise money for medical equipment in hospitals.
He was hospitalized for serious abdominal injuries and underwent five hours of surgery.
Before he was stabbed, Adamowicz had reportedly posted a picture from the stage on Instagram.
Meanwhile, a 27-year-old suspect with a criminal record has been arrested over the attack. Police believe he used a media pass to gain access to the stage.
Local television footage showed the suspect, who was recently released from prison, brandishing a weapon and shouting.
He reportedly said “Adamowicz is dead” and that the Civic Platform party, which led the previous government and supported Adamowicz’s re-election, had imprisoned him unjustly.
The suspect also claimed to have been tortured behind bars.
The Poland’s health minister on Monday, confirmed that Adamowicz had died from his injuries.
“We couldn’t win,” Lukasz Szumowski told local media.
Prime Minister, Mateusz Morawiecki, in a tweet on Monday, described Adamowicz’s murder as a “huge tragedy” for the country.
The mayor, who had lived in the city for 20 years, was known for his liberal views and opposition to Poland’s ruling Law and Justice (PiS) party.
Anti-violence rallies are being planned across the country in response to the attack.