Sao Paulo, Jun 5 (EFE).- A strike on Thursday disrupted metro service here in Brazil's largest city, leading to traffic backups and a riot by angry commuters at one station just a week before Sao Paulo is due to host the opening match of the 2014 soccer World Cup.
Nearly 5 million people ride the metro every day and the partial shutdown of four of the system's five lines resulted in gridlock across more than 200 kilometers (120 miles) of city streets.
The municipal government mobilized additional buses, but thousands of people were left with no way to get to work.
Commuters at the Itaquera metro station forced their way inside and vandalized the premises before police arrived and cleared them out.
The union representing the metro's 9,800 employees voted to strike after management offered a raise of 8.7 percent, well short of the workers' demand for a 16 percent pay hike.
The walkout affects four of the five metro lines. The fifth, which is run by a private company, was functioning normally Thursday.
Some trains continued to run on the other four lines, as supervisory personnel filled in for missing union workers.
Around 98 percent of employees are adhering to the strike, union secretary-general Alex Fernandes said.
Public sector unions in the 12 Brazilian cities hosting World Cup matches have been taking advantage of the approach of the June 12-July 13 competition to press demands for higher pay.
Sao Paulo authorities expect some 50,000 fans will rely on the metro to reach Arena Corinthians stadium for next Thursday's kickoff match between Croatia and five-time World Cup champion Brazil.
The metro strike comes two weeks after Sao Paulo bus drivers walked off the job for four days.