Thousands of demonstrators across Brazil have resumed their protests despite President Dilma Rousseff's promise to respond to their concerns about corruption and poor public services.
Trouble was reported in Belo Horizonte and Salvador, the two cities hosting Confederations Cup football matches on Saturday.
Smaller protests were also taking place in dozens of other cities, the BBC reports.
Brazil has been through more than a week of unrest, sparked by an increase in public transport fares in Sao Paulo.
The demonstrations quickly grew into nationwide rallies encompassing a raft of issues, from corruption and the poor quality of public services to the cost of hosting the current Confederations Cup and next year's Fifa World Cup.
President Rousseff announced several reforms on Friday as she tried to bring an end to the unrest.
She said she would draft a new plan to benefit public transport and that all oil royalties would be used in education.
A crowd gathered in the centre of Belo Horizonte on Saturday and marched towards the Mineirao stadium, where Mexico were playing Japan in the Confederations Cup, the eight-team football tournament seen as a curtain-raiser for next year's main event.
Police put the number of protesters at more than 60,000 people.
The clashes began when a group tried to break through a perimeter set by the police and the National Guard around the stadium. Riot police responded with tear gas and rubber bullets.
The trouble escalated after dark when car dealers had windows broken, some shops were looted and protesters set fire to a car and several other objects on the streets.
Authorities sent in mounted police officers and fired more tear gas to disperse the crowd.