Fans of Independiente and Universidad de Chile clashed at the Libertadores de America stadium during the second leg of their Copa Sudamericana last 16 tie on Wednesday.
Trouble flared at half-time when Universidad de Chile fans began throwing objects — including broken seats, pieces of masonry, and bottles — from the away section onto home fans housed a tier below.
As the second half got underway, the situation deteriorated further. Furious Independiente fans armed with belts, sticks and iron bars charged into the away section, attacking the visiting contingent. Some Universidad de Chile fans were brutally beaten and stripped of their clothing.
The game was abandoned with the score at 1-1 and the Chilean side leading 2-1 on aggregate.
At least 20 people were injured, including one in critical condition, and more than 90 people were arrested.
