Dundalk have promised to issue lengthy bans to the fans who "let the club down" in the aftermath of Saturday night's EA Sports Cup final against Derry City.
The Lilywhites won on penalties at the Ryan McBride Brandywell Stadium after a see-saw clash had ended 2-2 following extra-time.
Chris Shields struck the winning spot-kick to spark wild celebrations in the Dundalk end, with some supporters spilling on to the pitch and getting involved in a few unsavoury skirmishes.
The Louth club responded with a statement strongly condemning the scenes.
"At a time of celebration for the team and the vast majority of supporters, this small number of troublemakers let the club down with their behaviour," it read.
"The club does not condone any spectators invading the playing surface. We are seeking to identify the perpetrators and, in particular, those who subsequently clashed with Derry City supporters on and off the pitch.
"Dundalk Football Club is proud to be an inclusive, family-orientated club. Anyone who wishes to behave in the way we sadly witnessed on Saturday is not welcome at the club. We do not need their support.
"We have already identified four of the main instigators, each of whom will receive lengthy bans from attending any matches at Oriel Park.
"We are continuing to investigate the incident and appeal to any supporters who can help identify any of the troublemakers. If you have names, photos or social media footage of those people involved, please bring this to the attention of Dundalk Football Club to help with our investigations.
"We would like to put on record our thanks to the overwhelming majority of supporters for their behaviour on Saturday night. You traveled a long distance for a late kick-off time in huge numbers and your loud and constant support of the team throughout the game was fantastic, as it has been all season.
"Furthermore, the anger that you directed at those who let the club down as they returned to the stand spoke for all true Dundalk supporters, whose reputation should not be tarnished by the behaviour of a small minority of troublemakers."