Just hours before the 2014 World Cup kicks off in Brazil, Sao Paulo has been once again been marred by demonstration against the money spent on the tournament. Police fired tear gas, stun grenades and rubber bullets to try and break up the mass demonstrations which centred around the Caaro metro station. Military helicopters flew around the city as police attempted to disperse the 100-strong crowd with rubber truncheons. VIDEO Scroll down to see tear gas used on the opening day of the World Cup in Sao Paulo Clash: A woman is pushed by riot policemen during a clash with demonstrators in Sao Paulo, Brazil
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Violent demonstrations affect Brazil's Sao Paulo hours before World Cup
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Police fired tear gas, stun grenades and rubber bullets at 100 protestors
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Military helicopters flew over the city as protestors blocked major highway
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Two CNN journalists were injured, one with a suspected broken arm
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Brazil face Croatia in the opener this evening at Arena de Sao Paulo
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ITV studio glass cracked by rocks thrown at window during match
Clashes: Riot police fire tear gas during the demonstrations as they to calm the scenes in @placeholder