圣保罗警方向抗议者使用催泪弹
Brazilian riot police have used tear gas against protesters in Sao Paulo, three days before the World Cup opening game in the city's main stadium.
巴西防暴警察向圣保罗城内的抗议者施放催泪瓦斯，三天后世界杯将在该市主体育场内开赛。
The BBC's Katy Watson at the scene said about 300 demonstrators were there and helicopters circled overhead.
Sao Paulo metro workers, who called the protest, have since suspended a strike over demands for a salary increase.
Brazilian President Dilma Rousseff has said she would not allow violent demonstrations to mar the World Cup.
The strike, which began last Thursday, has caused widespread disruption in one of the world's most congested cities.
A union spokeswoman told the BBC on Monday that they had suspended the strike for two days to allow for negotiations and that protesters would meet again on Wednesday to consider their position.
If staff threatened with dismissal were not reinstated（恢复，复职）, she added, the protest would resume on the opening day of the World Cup.