The whistle marking the end of the match became the starting gun for the riot.
Hundreds of fans draped in the Spanish flag rushed out of the stands, pouncing like hungry wolves at the Latino fans gathered outside the stadium.
A teenager wearing a Guardiola jersey hadn't reacted yet before his hair was grabbed, pressing him to the ground, fists and heels rained down on his back like a storm. Several Colombian exchange students tried to shield their companion but were struck hard on the waist with a flagpole, leaving them curled up on the ground in pain. More people rushed into a nearby snack stand, overturning the cart of an old Mexican man, spilling hot tortillas and chili sauce all over the old man's body, exchanged for shouts of "Get out of Spain."
The sound of police sirens approached from afar, but the arriving officers seemed to have received some covert signal.
