Celtic face punishment from UEFA after fans waved the Palestinian flag during the club's Champions League play-off fixture against Hapoel Be'er Sheva of Israel.
Fans had been warned prior to the match that any political protest inside Celtic Park would be subject to censure from European football’s governing body and could result in a fine or even stadium closure.
Celtic have previously been punished by UEFA for waving flags deemed inappropriate and are likely, therefore, to be sanctioned again.
Scottish law also dictates that any individual found guilty could be arrested. Although waving such a flag would not in itself be punishable, the political implication behind the protests could mean they are deemed to have "stirred up hatred against a group of persons based on their membership (or presumed membership) of a group".
This was confirmed by Police Scotland superintendent Alan Murray, who told the Scottish Sunon Tuesday: "At every match, police will monitor the behaviour of the crowd, including any flags or banners displayed, and make a judgement on whether there is criminality and take the appropriate action."
Prior to kick off, a large group of Celtic fans confronted their Israeli counterparts outside the stadium, which led to police intervention.