Brazilian police are investigating a possible bomb placed in a backpack thrown outside the Supreme Court, the country's highest tribunal reported Thursday, three days before presidential elections begin.
The suspect, who was arrested, "tried to jump the court's fences" and "threw a backpack on top of a bus stop," the court said in a statement.
Police restricted access to the site, where an AFP journalist observed around a dozen patrol cars.
A bomb squad was on its way, military police reported, and spokesperson Raphael Broocke told AFP a "rigorous procedure to inspect the object" would take place.
Election campaigning in Latin America's largest democracy has been tense, with polls showing a dead heat between leftist incumbent Luiz Inacio Lula da Silva and Senator Flavio Bolsonaro in a potential runoff.
The pair will face off in a first-round vote on Sunday, with Lula projected as slightly ahead of his right-wing rival.
The Supreme Court is highly criticized by the political right, notably for the 2025 conviction of ex-leader Jair Bolsonaro -- Flavio's father -- for plotting a coup.
The institution has also become embroiled in a massive fraud scandal that has dominated the final weeks of the presidential campaign.
A man killed himself in a suicide bombing in front of the tribunal in November 2024.
The court was also a target during right-wing rioting on January 8, 2023, when Jair Bolsonaro supporters stormed several buildings hosting branches of government.
The Supreme Court later deemed the event an attempted coup against Lula's presidential victory over Bolsonaro senior that year.