Violence broke out in Brazil's capital city on 12 December 2022 as supporters of former President Jair Bolsonaro clashed with police.
Protestors were accused of trying to invade the federal police's headquarters in Brasilia, and also setting fire to many vehicles.
Hours earlier, Brazil's electoral authority awarded President-elect Luiz Inácio Lula da Silva an official certification, sealing his victory.
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Bolsonaro lost the election to da Silva in October, but the ex-President's supporters have challenged the result, calling for an intervention by the armed forces.
"The depredation and attempted invasion of the Federal Police building in Brasilia are unacceptable," said Flavio Dino, future Justice and Public Security Minister in the upcoming administration of President-elect Luiz Inácio Lula da Silva.
Police in full gear were rushed to the Federal Police's headquarters as back up, as officers had to use stun grenades and rubber bullets, local media reported. Police also blocked several avenues and streets across Brasilia.
Protesters elsewhere set at least one bus on fire and were seen gathering metal barriers.
(With PTI inputs)