Young Boys fans threw items such as broken seats and coins at Aston Villa players and police, with Dutch forward Donyell Malen being struck on the head.
The disorder occurred in the first half of the match, which Aston Villa won 2-1, prompting the deployment of numerous police officers in riot gear.
Superintendent Paul Minor condemned the violence, stating it would not be tolerated, and confirmed an investigation is underway, utilising body-worn video and CCTV footage.
This incident follows previous fines issued to Young Boys for similar supporter behaviour, including at Manchester City two years ago and Celtic in February.