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Demonstrations against the cost of the World Cup -- the most expensive and lucrative in history, with $11.5 billion having been spent by Brazil so far -- began when the country hosted the Confederations Cup last summer, and have continued.
Many feel the money would have been better spent addressing the country's problems with poverty, education, healthcare and transport -- but in a nationally televised speech last week, president Dilma Rousseff urged "pessimists" to back the tournament.
On Monday, protesters were joined by striking union workers as they called for more to be spent on education and healthcare. They claimed the government had put the World Cup above the well-being and safety of Brazilian citizens.
Their anger was fuelled by the heavy rainfall that has brought floods and landslides to some areas of Natal, and protester Daniele Gomez Silva, a student, told Reuters: "It seems the government is more worried about providing security to the Americans who are arriving to the stadium or making a good impression for the tourists."
The protesters were prevented from reaching the stadium by police.
Meanwhile, police in another host city, Curitiba, fired rubber bullets at demonstrators after another 200-strong anti-World Cup protest.
News website G1 reported that the protesters stopped a bus that was carrying fans to the Iran-Nigeria match and barricaded some streets with piles of burning rubbish.
After some protesters dispersed, others returned to the city centre. Police said the protesters attempted to storm banks before the rubber bullets were fired.