Media reports say one person has been killed and several injured when fans of two Bosnian soccer teams got into a fight before the start of a game on Sunday.
Bosnian TV says the fight erupted as soon as the Sarajevo soccer team fans arrived in the southern town of Siroki Brijeg on Sunday.
The station quoted witnesses as saying that shots could be heard and several vehicles were set on fire, including a police car.
Windows on nearby shops and private homes were smashed by stones the rival groups threw at each other.
Sarajevo fans are predominantly Muslim Bosnian, and fans of the Siroki Brijeg team are Catholic Croats from Bosnia.
The two were enemies during the 1992-95 Bosnian war and animosity from the conflict probably contributed to Sunday's clash.