RIO DE JANEIRO (AP) — Supporters of former Brazilian President Jair Bolsonaro who refuse to accept his election defeat stormed Congress, the Supreme Court and presidential palace in the capital on Sunday, a week after the inauguration of his leftist rival, President Luiz Inácio Lula da Silva.

Thousands of demonstrators bypassed security barricades, climbed on roofs, broke windows and invaded all three buildings, which are connected by the vast Three Powers Square in Brasilia. Some called for a military intervention to either restore the far-right Bolsonaro to power, or oust Lula from the presidency.

TV channel Globo News showed protesters roaming the presidential palace, many wearing the green and yellow colors of the national flag that also have come to symbolize the nation’s conservative movement, coopted by Bolsonaro.

The former president, who flew to the U.S. ahead of Lula’s inauguration, has not commented on Sunday’s events. The social media channels of his three lawmaker sons also were silent.

About 5:30 p.m. local time, less than three hours after the storming, security forces seemed to be regaining control of the presidential palace and Supreme Court’s surroundings, while thousands of protesters remained around Congress and on its roof.

The incidents recalled the Jan. 6, 2021, assault on the U.S. Capitol by supporters of then-President Donald Trump. Political analysts have warned for months that a similar storming was a possibility in Brazil, given that Bolsonaro has sown doubt about the reliability of the nation’s electronic voting system — without any evidence. The results were recognized as legitimate by politicians from across the spectrum, as well as dozens of foreign governments.

Unlike the 2021 attack in the U.S., it is likely that few officials were working in the Brazilian Congress and Supreme Court on a Sunday.

Videos on social media showed a limited presence of the capital’s military police; one showed officers standing by as people flooded into Congress, with one using his phone to record images. The capital’s security secretariat didn’t immediately respond to a request from The Associated Press for comment about the relative absence of the police.

“Brazilian authorities had two years to learn the lessons from the Capitol invasion and to prepare themselves for something similar in Brazil,” said Maurício Santoro, political science professor at the State University of Rio de Janeiro. “Local security forces in Brasilia failed in a systematic way to prevent and to respond to extremist actions in the city. And the new federal authorities, such as the ministers of justice and of defense, were not able to act in a decisive way.”

Federal District Gov. Ibaneis Rocha confirmed on Twitter that he had fired the capital city’s head of public security, Anderson Torres.

Bolsonaro supporters have been protesting Lula’s electoral win since Oct. 30, blocking roads, setting vehicles on fires and gathering outside military buildings, seeking the armed forces to intervene. Many of them alleged that election results were fraudulent or unreliable.

“This absurd attempt to impose their will by force will not prevail,” tweeted Justice Minister Flavio Dino. “The government of the Federal District has ensured there will be reinforcements. And the forces at our disposal are at work.”

Lower House Speaker Arthur Lira said on Twitter: “Congress has never denied a voice to those who want to demonstrate peacefully. But it will never give room for turmoil, destruction and vandalism.”