Four Russian football fans were being held for questioning in the northern French town of Lille ahead of the Euro 2016 match between Russia and Slovakia, police said on Wednesday.
Two of them were taken in during the night of Tuesday to Wednesday, having been found drunk in a car, while the other two were detained after fighting with English supporters on Tuesday.
The arrests came as thousands of fans arrived in Lille for Wednesday's match and for the England versus Wales game due to take place on Thursday in nearby Lens amid a heavy police presence and a ban on alcohol in attempts to prevent a repeat of violence that has marred the tournament.