Clashes in Brazil

ROUGH CUT (NO REPORTER NARRATION).

STORY: Demonstrations turned violent Tuesday night in Rio de Janeiro as thousands turned out to support teachers on strike for higher wages.

Tuesday was also national Teacher's Day throughout Brazil.

Teachers are currently striking in many states in Brazil, calling for better work conditions and salary increases.

But the longest and largest strike thus far has been the teachers' strike in the state of Rio de Janeiro, which began August 8.

As has been common since protesting first erupted in Brazil last June, the demonstration began peacefully but then turned confrontation as masked protesters, some dressed in black and calling themselves Black Bloc, engaged police and committed acts of vandalism.

The incident marked three consecutive weeks in Rio a teacher-related demonstration ended up in chaos and violence.