An assembly line at one of three General Motors plants in Brazil has ground to a halt as workers strike to protest the planned layoffs of nearly 800 employees.

The Metalworkers Union in Sao Jose dos Campos says that 5,200 workers went on strike Friday morning, stopping the daily production of 300 Chevrolet Trailblazers and S10 pickup trucks.

"The strike is the only way we can stop mass dismissals from taking place at GM," union president Antonio Ferreira de Barros said.

GM said in an emailed statement the union did not notify it of its plans to strike "as determined by law."

The company provided no further information.

GM's two other auto plants in Brazil were operating normally Friday.