Celtic have been fined £12,900 after fans displayed an "illicit banner" and sang obscene chants during their Europa League game at home to Lazio, reports BBC Sport.
The Italian club have also been fined £8,600 by European governing body Uefa for "illicit chants" during the 24 October meeting.
One banner from the home supporters depicted former Italian leader Benito Mussolini hanging upside down.
Another displayed swearing in Italian.
It is the 19th time Celtic have been punished since 2007 and their third charge this season.