Wolves fans in Portugal have reportedly been attacked by hooligans from Standard Liege ahead of respective Europa League clashes on Thursday.
Wolves are in Portugal to face Braga with around 6,000 supporters travelling to support the team, while Standard Liege are also in the vicinity as they play Vitoria SC.
With both matches taking place on the same evening with 15 miles between the stadiums, both sets of fans are believed to have congregated in nearby Porto and that has led to some Wolves supporters being attacked by Liege ultras, according to the Birmingham Mail.
The report states that at least one supporter is believed to have been taken to hospital due to his injuries.
A video has also emerged on social media of local police trying to keep control of the situation by firing rubber bullets.
Problems were anticipated due to the influx of supporters to the city, with thousands descending on the Portuguese coast.
One Wolves supporter tweeted: '150 Liege fans all in black just round the corner from where all the Wolves fans are down by the river. This is not going to end well...'
Wolves know a victory against Braga on Thursday will be enough to qualify for the knockout stages of the Europa League.
It would also mean they would leapfrog the Portuguese club in the table, ahead of their final group game at home to Besiktas on December 12.