Jairo Nicolau, a professor of political science at the Federal University of Rio de Janeiro, said the move to call in the armed forces was a “mistake.”
“It is a bad sign at this moment; it could signal weakness from the government,” Mr. Nicolau said. “We are in a moment of insecurity, and any act of this type creates more insecurity. We have had much worse demonstrations than this that were controlled by the police.”
Tensions have been rising in Brazil over a scandal engulfing Mr. Temer’s government, especially after a beef tycoon secretly recorded his discussion with the president about obstructing an anticorruption drive. The disclosure last week of the recording prompted a plunge in Brazil’s financial markets, an investigation of Mr. Temer and widespread calls for him to resign, but he has combatively refused to step down.
Brazilian news organizations reported on Wednesday that ministry buildings in Brasília were evacuated as a result of the protests, while a session of Congress was suspended after shouting matches erupted between opponents of Mr. Temer, 76, a centrist who has drifted to the right, and his supporters. Firefighters managed to control the blaze in the Agriculture Ministry.
The public security secretariat of Brazil’s Federal District, which includes Brasília, blamed protesters trying to get through a security cordon for the violence.
“Demonstrators tried to invade the security perimeter,” the secretariat said in a statement, but they were stopped by the police, “who used progressive force.”
Some demonstrators contested the official statement.
Vitor Guimarães, 26, an activist from the Landless Workers’ Movement, a militant leftist group, said that he was on the grassy area in front of Congress when the police attacked protesters.
“The main part of the…