LONDON — Police say three officers were injured while arresting violent fans ahead of the Champions League semifinal between Tottenham and Ajax.

The Metropolitan Police say a group of fans began throwing objects outside the north London stadium at around 7:15 p.m. local time on Tuesday— 45 minutes before kickoff.

Police officers intervened and arrested four people with three officers sustaining non-serious injuries.

Police said they made five additional arrests in other incidents before the first-leg semifinal, which Ajax won 1-0.