There were confrontations between rival fans inside Turf Moor following the full-time whistle of the Saturday's game between Burnley and Arsenal.
Supporters goaded each other over the barrier separating the away section from an area housing home fans after the game, which Arsenal won 1-0.
Missiles, including bottles, were also thrown by both groups.
An announcement to clear the area initially went unheeded, with crowds dispersing after around 10 minutes.
The only goal of the game was scored by Martin Odegaard in the first-half, with his free-kick beating both the wall and home goalkeeper Nick Pope.