Arsenal say they will work with both the authorities and Tottenham Hotspur to investigate an incident in which some of the club's travelling support ripped down hoardings at White Hart Lane following their 2-1 Capital One Cup third-round victory.
Kept behind after the game, some away fans pulled away parts of the "This Is Our Club" boards on the first tier of the Park Lane stand at Spurs.
An Arsenal spokesman said the club were "concerned" but stressed it involved a "small minority."
"We are concerned that this has happened involving a minority," the spokesman said. "We will work with Tottenham Hotspur and the authorities on this."