Brazil’s military staged an unusual convoy of troops and armored vehicles through the capital on Tuesday — an event announced only a day before and that coincided with a scheduled vote in Congress on one of President Jair Bolsonaro’s key proposals.

Scores of vehicles and hundreds of soldiers paraded past the presidential palace as Bolsonaro looked on, then continued past the congressional building and Defense Ministry.

The navy issued a statement saying the convoy had been planned long before the congressional vote. But it was announced only on Monday and critics said it looked like an attempt to intimidate opponents of a president who has often praised the country’s past military dictatorship.

Military parades in the capital are usually limited to independence day events. Tuesday’s procession was described as a ceremonial invitation for Bolsonaro to attend annual navy exercises that are held in a town outside the capital. The army and air force also are participating for the first time.

Congress’ lower house earlier had scheduled a Tuesday vote on constitutional reform that Bolsonaro has crusaded for: requiring printed receipts from some electronic ballot boxes that the president alleges are prone to fraud.

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The parade upset some lawmakers. Omar Aziz, the president of a Senate probe into the government’s COVID-19 pandemic response, said the parade was “a clear attempt to intimidate lawmakers and opponents. He (Bolsonaro) imagines he is showing strength, but he is showing a president weakened by investigations.”

Critics allege that Bolsonaro, who trails rivals in early opinion polls, is trying to sow doubt among his passionate supporters about the 2022 election results, setting the stage for potential conflicts similar to those spawned by former U.S. President Donald Trump’s allegations of fraud in the United States.

Bolsonaro’s son Eduardo, a lawmaker, on Monday reinforced the family’s close association with Trump by posting on social media what appeared to be a recent photo of himself standing alongside the former U.S. leader and saying he (Eduardo) is “on the side of men with unblemished reputations and the moral authority to walk down the street, head held high.”

Tuesday’s military procession shows Bolsonaro is either a poor judge of the political climate or is knowingly straining against democratic norms, said Kai Kenkel, a specialist on Brazil’s military at Rio de Janeiro’s Pontifical Catholic University.

“We still need to know for sure whether there is a connection between Bolsonaro’s agenda and the motivations of the navy to do this, because the navy has been much more careful not to make political statements,” Kenkel told The Associated Press.

Electoral authorities have repeatedly denied any problems with the voting system and Bolsonaro has failed to present proof despite a Supreme Court order to substantiate his allegations.

The president has repeatedly insulted Luis Roberto Barroso, a Supreme Court justice and the electoral court’s president, accusing him of working to benefit former leftist President Luiz Inacio Lula da Silva, who has been leading in the polls.

Tuesday’s measure is a watered-down version of an initial proposal to adopt printouts at all of the nation’s voting ballot boxes — a bill rejected last week by a congressional committee.

Electoral authorities and even many of Bolsonaro’s political allies oppose the plan, saying it attacks a nonexistent problem and would create opportunity for vote buying.

The call for a vote appeared to be a bid by lower house Speaker Arthur Lira, a Bolsonaro ally, to settle the dispute for good and ease tensions.

On Monday, Lira called the military exercise taking place the same day as the vote a “tragic coincidence.″

Bolsonaro has repeatedly hammered on the fraud claims to rally supporters and shows no sign of dropping the issue.

“We will do everything for our freedom, for clean, democratic elections and public count of votes,” he told backers Saturday at a rally in Santa Catarina state. Any election without that isn’t an election.”

He led another rally, a motorcycle convoy, in the capital on Sunday.

“It isn’t just now that there are rumors about fraud in the ballot boxes, but now there’s this proposal and he (Bolsonaro) resolved to go in head first,” said Maria da Silva, a 61-year-old homemaker from Sao Paulo. “I trust him.”

Juan Gonzalez, the U.S. National Security Council’s senior director for the Western Hemisphere, told reporters on Monday that Biden administration officials were “very candid” speaking last week with Bolsonaro about elections, particularly in light of parallels with what has happened in the U.S.

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“We were also very direct, expressing great confidence in the ability of the Brazilian institutions to carry out a free and fair election with proper safeguards in place and guard against fraud,” Gonzalez said. “And we stressed the importance of not undermining confidence in that process, especially since there were no signs of fraud in in prior elections.