BARCELONA - Barcelona fans celebrating the side's second consecutive La Liga title were involved in clashes with the police in the city centre late on Sunday night.
There were a total of 104 arrests and 119 people were treated for injuries, though none were serious, the local police said.
Some 40,000 fans congregated near the Canaletas fountain following Barca's 4-0 defeat of Real Valladolid at the Nou Camp, but the festive atmosphere turned ugly after midnight.
Some people started trying to pull down a huge advertising poster attached to scaffolding across the front of a building in the square, and set parts of it alight.
The police moved in and for a while thereafter there were running battles in the streets, with missiles being thrown, phone booths being smashed and bins being set alight in the city centre.