Police said that 95 hooligans arrested in downtown Paris -- all of them Dutch -- were armed with iron sticks, knuckledusters and ski masks found by police in the bars where they were gathered.
Forty-one supporters were released overnight while 54 remained in custody on Tuesday morning.
French authorities fear some 200 to 300 Dutch hooligans have made the trip, in addition to the 850 ticket-holding members of Ajax's official travelling support, in the hope of clashing with their Parisian counterparts.
Though PSG have taken steps to neutralise the more violent factions of its support since running battles in the Paris streets between home supporters and FC Twente fans before and after the clubs' 2008 Europa League encounter, hooliganism remains a problem for the French champions outside their stadium.
Police have special powers (is it legal?!) to stop and arrest any Ajax fan around the Parc des Princes who is not in possession of a ticket, and have been exercising that right since Sunday afternoon, checking arrivals by train and plane.