Brazilian riot police have used tear gas against about 300 protesters in Sao Paulo, three days before the World Cup opening game in the city's main stadium.
The protest was called by Sao Paulo metro workers who are striking in support of a 12.2 per cent salary increase.
Brazilian President, Dilma Rousseff, has said she would not allow violent demonstrations to mar the World Cup.
Sao Paulo metro workers have been on strike since Thursday last week, creating traffic chaos in one of the world's most congested cities.
The President of the Metro Workers Union organising the strike, Altino Prazeres, said that ruining the World Cup was not the strikers' intention.
"I love soccer! I support our national team. The point is not to stop the World Cup,'' he told the AP news agency yesterday.
"We want to resolve this today and all are willing to negotiate," he said.
The state subway company has offered an 8.8 per cent pay rise but this has been rejected by the strikers.
On Sunday, union members voted to continue to strike indefinitely despite a court order for them to return to work and a threat of dismissal by the state governor.
On Monday, a spokesman for the company that runs the metro said 60 dismissal notices had been sent out to staff alleged to have been involved in strike-related disturbances in recent days.
However, the company could not confirm that these notices had been received or had taken effect.
BBC correspondent in Sao Paulo said that police dispersed the protesters but that it was clear there was a great deal of bitterness about the money spent on the tournament.
If the strike runs on until Thursday, it could affect the opening match between hosts Brazil and Croatia.
Arena Corinthians Stadium is on the outskirts of Sao Paulo and access to the venue without public transport could be a huge challenge for fans.
Preparations for the World Cup have been beset by construction delays and strikes but President Rousseff has said her government would "fully guarantee people's security" during the tournament.
Thousands of extra police and soldiers will be deployed to ensure the matches get under way smoothly.
Last year, more than a million people took to the streets of major Brazilian cities to vent their anger at what they see as excessive spending on the World Cup and the 2016 Olympics in Rio.
The government is keen to prevent a repeat of some of the violence seen at those protests.