Franz Ferdinand fans were reportedly tear gassed during the band's headline set at a festival.
Crowds watching the act at a music event in Sao Paulo, Brazil on Sunday (May 27) faced tough security measures to stop fans breaking down perimeter fences, reports Metro.
"There was no organisation. Everyone started pushing forward trying to get in," Thamys Porto told the Folha de Sao Paulo newspaper.
"That's when they closed the gates. There was panic. The riot police tried to make a human chain, but they couldn't contain them, so they began throwing tear gas into the crowd."
He added: "I couldn't breathe or open my eyes. We tried to find medical help but there was none."
Following the incident, Franz Ferdinand singer Alex Kapranos tweeted: "Hope any fans caught outside gig tonight were OK and weren't hurt in the collision with police. We knew nothing of this. Awful news."
Kapranos later told another fan: "That's terrible. I wish there was something I could do."