Celtic fans were attacked outside a pub in Rome ahead of their side's Europa League meeting against Lazio on Thursday night.
Karpaty Lviv and St. Etienne hools clashed in a mass fight in the western Ukrainian city of Lviv on Wednesday night ahead of the French side's match against Oleksandriya in the Europa League.
Valerenga fans pinched a flag from the Brann section before kick-off in their Eliteserien clash on Sunday.
Persebaya Surabaya fans rioted at the Gelora Bung Tomo stadium after their side's 3-2 loss to PSS Sleman on Tuesday.
Young Boys and Feyenoord fans clashed briefly in the Swiss capital on Thursday ahead of their Europa League fixture.
Olympiacos hooligans attacked Bayern Munich fans during an Under-19 match between the two sides at the Greek club's training complex on Tuesday evening.
Fighting broke out between Atletico San Luis and Queretaro fans in the stands during their Liga MX match on Sunday.
Cagliari and Pogon Szczecin hooligans clashed in the streets of the Sardinian capital after a friendly between the two sides on Friday.
England fans clashed with riot cops in Prague on Friday evening ahead of the Three Lions’ Euro 2020 qualifier against the Czech Republic.
An Ukrainian First League match between Balkany Zorya and Chornomorets Odesa was abandoned on Saturday after the Odesa side's fans clashed with stewards and police.
Fighting broke out between rival sets of Tirana and Partizani fans inside the Selman Stermasi Stadium before the start of their derby match on Sunday.
Widzew Lodz's Polish cup match against Slask Wroclaw was stopped for several minutes on Tuesday after trouble broke out in the away end.