They were attacked by a group of around 30 individuals – reportedly believed to be locals and in no way linked to travelling Villarreal fans.
The Polish city is hosting the final, which takes place tonight at 8pm.
A video published on social media shows a group of individuals gathering outside a bar in the city, which contained United fans, with tables and chairs overturned in the aftermath.
United released a club statement this morning, saying: “Club staff were assisting a number of United fans in Gdansk last night and today after an incident where some of our supporters were attacked outside a bar in the city.”
BBC journalist Simon Stone tweeted that some fans were the victim of theft during the attack, and that he is not aware of any issues involving United/Villarreal fans prior to the final.
The Athletic reported that the mayor of Gdansk, Aleksandra Dulkiewicz has apologised for the incident.
She said there is “no place for any kind of violence” in Gdansk, and that she is in contact with police, who are establishing the details of the incident.
“Dear Manchester United and Villarreal fans, all guests who came to Gdansk – you are always appreciated here and we cordially welcome you to our city.”
United have been allocated 2,000 tickets for the final, with half of the fans said to be arriving in the Polish city today.
Ole Gunnar Solskjaer‘s side are looking to claim their first trophy in four years – exactly 21 years after the Norwegian scored the winning goal in the famous 1999 Champions League final against Bayern Munich.
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