Clashes in Rio and Sao Paulo after Brazil teacher protest
16 October 2013 Last updated at 06:41 BST
Protesters have clashed with the police in the Brazilian cities of Rio de Janeiro and Sao Paulo following marches in support of striking teachers.
Soon after a peaceful demonstration by more than 5,000 people passed by peacefully in Rio, smaller groups of masked activists attacked shops, setting fire to a police car and throwing petrol bombs.
Police responded with tear and pepper gas and detained dozens of people.