CONMEBOL opened an investigation after Uruguay players clashed with Colombian fans at the end of their Copa America semi-final match on Wednesday, the South American soccer governing body said.
After Colombia sealed a 1-0 victory in Charlotte, North Carolina, videos on social media showed what appeared to be Uruguay players climbing into the stands and exchanging blows with opposition fans, according to a Reuters report.
Uruguay's Darwin Nunez and Ronald Araujo were among the players at the forefront of the melee. Captain Jose Maria Gimenez said the players were trying to defend their families.
Players and staff from both Colombia and Uruguay were also involved in a confrontation on the field after the final whistle.
"CONMEBOL has opened an investigation to understand the sequence of events and the responsibilities of those involved in the acts of violence that occurred at the end of the match," CONMEBOL said in a statement on Thursday.
"We want to reaffirm and warn that no action will be tolerated that tarnishes this global football celebration.
"It is unacceptable that an incident like this turns passion into violence. Therefore, no behavior that harms the sporting competition will be tolerated."