Fans of Morocco's Wydad Casablanca clashed with police inside the Mohammed V stadium after their match against arch-rivals Raja on Saturday.
Vardar fans clashed with police in the first half of the match.
Partizan hooligans pinched some flags belonging to Augsburg fans during Thursday's Europa League match in Belgrade.
Irate Levski fans clashed with riot police after a defeat of their team.
Santiago Wanderers and Colo-Colo fans clashed at the Elias Figueroa Brander stadium before their Primera Division match on Sunday.
Trouble flared at the end of Sunday's game between Lugano and Grasshoppers when supporters came on to the pitch.
CSKA Sofia hools caused problems at the third league match against Minyor Pernik.
Sonnenhof Großaspach's match with 1. FC Magdeburg was interrupted for several minutes on Saturday afternoon after away fans clashed with stewards.
Schalke fans clashed with Bayern Munich fans ahead of their Bundesliga match at Arena AufSchalke on Saturday evening.
Panathinaikos hooligans clashed with riot cops at the Apostolos Nikolaidis Stadium after their match against arch-rivals Olympiacos was called off.
Los Andes fans clashed among themselves and police during the match.
During the Promień Żary vs. UKP Zielona Góra match on Saturday in Poland, home fans stormed the pitch and attempted to get to the away end.