RIO DE JANEIRO — The explosions that shook Brazil’s capital Wednesday evening and prompted an evacuation were an act of terrorism by a lone attacker who sought to violently disrupt democracy, police officials said Thursday.

Authorities said the only person killed was the attacker, and no one was injured. But the two explosions took place near the nation’s Supreme Court in Brasília, the capital, and put the nation on edge just days before the country is set to host a major Group of 20 summit, which President Joe Biden and other world leaders are expected to attend.

The attack echoed the violence that descended on Brasília after the election of President Luiz Inácio Lula da Silva nearly two years ago, fueling worries about renewed tensions after a period of relative calm. While tensions have subsided since, Brazil’s far right has appeared energized in the days since President-elect Donald Trump’s sweeping return to power in the United States.

Authorities identified the attacker as Francisco Wanderley Luiz, 59.

— The New York Times