Fighting between Poland and Russia fans in Warsaw ahead of Tuesday's Euro 2012 match forced police to intervene, with several people injured.
Russian supporters clashed with police and Poland fans in a number of incidents, just hours before the two teams were to meet in Group A of the tournament.
Several people were reported to be lying injured and bleeding on the ground in the Polish capital after violence between the sets of fans.
Supporters were also seen fighting and throwing stones outside the Warsaw National Stadium.
More incidents came as Russia fans marched to the stadium waving their country's flag in a show of patriotism, which was seen as provocative by many Poles.
The two countries share a difficult history, including decades of Moscow's control over Poland during the Cold War.