Supporters of Brazil's defeated Jair Bolsonaro attack police headquarters

Brazil Violence: Federal police said "disturbances" near the headquarters were being handled with support from capital security forces.

Supporters of far-right Brazilian President Jair Bolsonaro on Monday attempted to invade the federal police headquarters in the capital Brasilia, in a flash of post-election violence on the day the president's electoral defeat was certified.

Brazil Violence: Brazil's former president Jair Bolsonaro.(Reuters)

Reuters witnesses saw Bolsonaro supporters, many in their trademark yellow national soccer jerseys or draped in Brazilian flags, confronting security forces at police headquarters. Police fired stun grenades and tear gas to disperse the crowd. Nearby buses and cars were set on fire.

Federal police said "disturbances" near the headquarters were being handled with support from capital security forces.

The violence unfolded after a Bolsonaro supporter was detained for allegedly organizing violent "anti-democratic acts," according to the judge who ordered his arrest.

Earlier on Monday, the federal electoral court (TSE) certified the Oct. 30 election victory of Bolsonaro's leftist rival, Luiz Inacio Lula da Silva, as president. After months of baseless suggestions that Brazil's voting system is vulnerable to fraud, Bolsonaro has neither conceded defeat to Lula nor has he formally blocked the handover of power.

But some of the president's most diehard supporters have blocked highways in protest and camped out in front of army barracks, calling for a military coup to bar Lula from office.

Hundreds of Bolsonaro supporters gathered outside the presidential residence on Monday afternoon with banners calling for "military intervention." The president joined them for a public prayer but did not address the crowd.

"There's not going to be an inauguration," said Jose Trindade, 58, one of the Bolsonaro supporters in the crowd. "Bolsonaro was re-elected, but they stole it. So only the army can put things in order."

The conspiracy theories and subsequent violence have rekindled memories of the January 2021 invasion of the U.S. Capitol by supporters of former U.S. President Donald Trump. It also raises security concerns about Jan. 1, when Lula takes office in a public ceremony in Brasilia.

Senator Randolfe Rodrigues, a key Lula aide, said there were concerns about the physical safety of Lula and Vice President-elect Geraldo Alckmin, as protesters had surrounded the hotel where he is staying in Brasilia. Lula's team denied reports that Lula would be removed from the hotel by helicopter.

Brasilia's public security officials said they had secured the area around Lula's hotel, and urged motorists to avoid the center of the city where many roads had been closed.