The Football Association is to investigate the post-match clash between Burnley and Arsenal fans at Turf Moor on Saturday.
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 FA will look into the incident in order to establish further details.
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.
Burnley are now winless in their last 13 Premier League home games and have picked up just one point from five matches this season.
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Source: www.bbc.com