Clashes in Rio and Sao Paulo after Brazil teacher protest

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.