President Dilma Rousseff's impeachment

More than a million Brazilians have joined demonstrations demanding President Dilma Rousseff's impeachment.

The protesters say the president must have known about a corruption scandal which has engulfed Brazil's state-owned oil company, Petrobras.

The political opposition says much of the alleged bribery took place when she was head of the company.

But Ms Rousseff has been exonerated in an investigation by the attorney general and denies involvement.