Celtic fans have been attacked with batons, riot shields and rubber bullets by police in Valencia, it has been claimed.
People as young as 15 were allegedly hurt before the club’s Europa League game against the Spanish club on Thursday.
Witnesses on Wednesday night said they did not see any signs of provocation.
Davy Macnamara was with his 15 and 21-year-old sons at St Patrick’s Bar in the city, the youngest of whom he said was struck with a baton as they ran from police.
He said his son heard of a friend’s sister who was “beaten black and blue” with truncheons and is now looking for a flight to get home before the match takes place on Thursday evening.
Sky News reported police in Valencia, the Jefatura Superior de Policia, told them six Celtic fans have been arrested following altercations, five detained for disorderly conduct and one for alleged drug trafficking.
“It was terrifying to be involved in, it’s just horrible to be here as a dad stuck in an apartment, scared to go out in the streets in case it kicks off again,” Mr Macnamara, 47, told the Press Association.
Scott Tobin was at the same bar and said he saw an elderly man being beaten with a baton and also heard of a 15-year-old girl being taken to hospital.
“It was quite scary, they were chasing us down the street with their riot gear on,” the 26-year-old from Glasgow said.
“We didn’t know what would happen if they caught us.”
Several fans shared images on social media of bruises they said were sustained from guns with rubber bullets.
“I had never seen one in my life and it’s horrifying to be faced with that,” Mr Macnamara, a roofer from Dunfermline, Fife, said.
He added fans were “filled with joy” in the bar and “didn’t see one bit of trouble” but outside there were riot police waiting for them with some fans in handcuffs.
Police ushered them up one street to a crossroads where there were more Celtic fans running from police, he said.
“I said to my boys ‘there’s no point in running, we’ve not done anything and there’s more police back the way we came’ but then the police started marching towards us in a line,” Mr Macnamara added.
“We stood in the middle of the street with our hands up and they charged us, and as we ran my 15-year-old son was struck in the back with a baton.”
He said another man near him was hit to the ground after a policeman struck his legs.
Mr Macnamara said he and his sons ran down the street to escape the crowd, turning their jerseys inside out so that they would not be recognised as Celtic supporters and managing to escape the police shortly after.
“I’ve been to Seville, Portugal and all different countries to watch Celtic and I wouldn’t have brought a 15-year-old if I had thought there was going to be any trouble,” he said.
“I never even saw a Valencia fan and you would have thought there would have been troubles and riots.
“I’m absolutely gutted, there was no need for it and tonight will be even worse.
“If Celtic had rioted and broken glasses I might understand but I didn’t see anything, we were singing and happy.
“I’m here to make memories with my two boys and it’s the wrong memories.
“I should be enjoying the sunshine with my fellow Hoops supporters.”
Daniel McKenna, 20, filmed a policeman apparently hitting a fan with a baton while they were lying on the ground before crushing their headphones underfoot.
“Their presence was expected as deterrents if anything did happen but it seemed as if they were looking for trouble themselves,” the University of Strathclyde student said.
On Thursday, Valencia said in a statement they have closed their match day ticket office due to fan safety concerns.
The Press Association contacted local police for comment but they had not responded with a statement by the time of publication.