Riot police and search helicopters have been used to try and deal with the escalating protests, which claimed the life of an 18-year-old man when a car drove into barricades in Sao Paulo.

The riots began over a week ago over the cost of high transport fares, but are also reportedly in response to public corruption, lack of health and education services and high taxes.

There are eight games left in the Cup, culminating with the final on June 30, and FIFA media representative Pekka Odriozola has attempted to quell fears the tournament would be halted early.

"At no stage has FIFA considered or discussed abandoning the Confederations Cup with the local authorities," Odriozola said on Friday.

"We are monitoring the situation with the authorities.

"We support the right of free speech.

"We condemn violence."

Brazil president Dilma Rousseff has cancelled a trip to Japan to hold emergency meetings with cabinet members.