UEFA has opened disciplinary proceedings against Celtic following alleged crowd disturbances during their match against Dinamo Zagreb.
A hearing into the matter will be held by UEFA's Control, Ethics and Disciplinary Body on February 19.
It is understood that fans of the Scottish champions lit flares and clashed with riot police during their team's 4-3 defeat in the Europa League last week.
Celtic are back in league action on Sunday when they make the trip to Dundee United.