Police made 25 arrests after Leeds United's pre-season friendly against Eintracht Frankfurt in Austria erupted into violence on Tuesday.
A number of arrests were made prior to kick-off, but tempers flared further after the final whistle when Leeds fans entered the field of play and headed in the direction of opposition supporters.
That provoked an angry reaction from some spectators in the Frankfurt end of Sportzentrum Eugendorf, with violence spilling over onto the pitch and out of the ground.
At least five people, including two police officers, were injured during the clashes, while the majority of those arrested were Frankfurt fans.
A statement from local police revealed an investigation is ongoing.
Frankfurt won the encounter 2-1.
