England play Serbia in Group C of the UEFA European Football Championship in Germany.

On Sunday, social media footage showed men throwing chairs at each other outside a restaurant festooned with Serbian flags in the western city of Gelsenkirchen. One group beat a hasty retreat as riot police arrived and wrestled at least one man to the ground.

A Serbian fan told The Associated Press that a group of people had thrown glasses and stones at the area outside a downtown bar where he and others were sitting together drinking beer.

“There was a clash and we are fine. So that’s it, we are going to the game, we hope we will win. This is about football,” said the man, who identified himself only as Vladimir and said he was from the Serbian capital Belgrade.

Reporters who arrived shortly after the incident found the street littered with broken glass and tables as several dozen police officers stood by.

The match on Sunday evening between England and Serbia has been tagged “high risk” by police over concerns over potential fan violence.

“So far what ‘high risk’ means practically is that lower-alcohol drinks will be sold and no alcohol at all can be drunk inside the stands in the stadium,” Al Jazeera’s Dominic Kane said, reporting from Munich.

Only low-alcohol beer is being served in the Gelsenkirchen stadium in an attempt to reduce the potential for problems.

“One complicating factor is that UEFA, the parent organisation of these championships, has said that the barriers inside the stadium have to be removed … that suggests the English and Serbian fans could be intermingling inside the stadium,” Kane noted, adding that the German police have been putting in a lot of effort to prevent such hooligan scuffles.

About 20,000 England fans and 10,000 from Serbia are expected to converge on the city for the game.

The match will be played at Arena AufSchalke and starts at 9pm local time (19:00 GMT).