Violent clashes between fans and police caused the abandonment of a match between the top two sides in Paraguay on Sunday.
Hundreds of spectators escaped onto the pitch as police fired rubber bullets and tear gas into the stands at the Superclasico, played between Olimpia and Cerro Porteno, both based in capital city Asuncion.
According to witnesses, the trouble began when firecrackers were detonated in the section of the Defensores del Chaco Stadium which was allocated to Cerro Porteno supporters.
The police detained around 100 people, and while it was not immediately clear whether any fans had been injured, security forces reported that at least six officers were hurt, with one in a serious condition.
David Torales, a spokesperson for a local hospital, said the “officers sustained head injuries, lacerations, including possible stab wounds, and other injuries”.