More than 200 supporters of Peñarol were detained Wednesday after clashing with law enforcement ahead of their team's Copa Libertadores semifinal match against Botafogo, Rio de Janeiro police said.
Police said in a statement that the fans "were involved in a series of acts of vandalism, looting and destruction of business places and vehicles." One pistol was found, police said.
TV footage showed people dressed in Peñarol shirts throwing stones at police officers, defending themselves with tables taken from local kiosks, and setting motorcycles on fire near a beach in Rio's west end. The conflict lasted more than one hour.
According to police, the violence began when a Uruguayan fan was arrested for stealing a cellphone in a bakery in the Recreio Beach area on the west side of the city.
Peñarol fans fought with police on the same beach before a game against Flamengo last month.
In 2019, a Flamengo supporter died in a clash between Peñarol and Flamengo fans in Rio.
The bus carrying Peñarol's team to the Nilton Santos stadium was delayed by two hours, with club president Ignacio Ruglio saying the vehicle had been attacked.
"They brought us at a pedestrian pace for almost two hours, the places where they put us, the stones they threw at us, they put us in the middle of the corral," Ruglio told reporters after arriving at the venue.
"Today, nobody really controlled anything."
Ruglio added that Conmebol, South American football's governing body, told them the delay was "incomprehensible" and agreed to push the start of the match back by 15 minutes to 9:45 p.m. (1245 GMT)
Peñarol fans also fought with police on the same beach before a game against Flamengo last month, and in 2019, a Flamengo supporter died in a clash between Penarol and Flamengo fans in Rio.
Later Wednesday, Botafogo beat Peñarol 5-0 for the first leg of their semifinal.
Information from Reuters and The Associated Press was used in this story.