Clashes broke out in Rio de Janeiro in Brazil last night as striking teachers and their supporters took to the streets.
Organisers rallied thousands in Rio's centre to demonstrate for the city's teachers, who are demanding pay increases.
Protesters also spoke out against what many considered to be an excessive use of police force on demonstrating teachers a week ago.
The protest began peacefully, with demonstrators occupying one of Rio's major streets.
According to police, 10,000 protesters filled the streets but the teachers' union put the crowd at 50,000.
As the evening wore on, the scene turned into an exchange of police firing tear gas and protesters throwing stones and Molotov cocktails.
Masked demonstrators lit fire to rubbish and broke store front windows.
The incident comes one week after a similar teacher demonstration also descended into chaos and clashes.