Chaos struck Brazil's capital Sunday when supporters of far right former President Jair Bolsonaro descended on government buildings, breached them, climbed on a rooftop and broke windows.
Video depicted damage to an office in the presidential palace, as well as broken windows in the country's highest court.
Leftist President Luiz Inácio Lula da Silva, sworn in Jan. 1, responded by authorizing federal intervention in the Federal District until the end of January.
He called those who attacked Congress “fascists,” according to translations of his tweets Sunday.
“Whoever did this will be found and punished. Democracy guarantees the right to free expression, but it also requires people to respect institutions,” Lula tweeted. “There is no precedent in the history of the country what they did today. For that they must be punished.”
Authorities used tear gas and clashed with the demonstrators, according to video from the scene distributed by news organization Reuters.
Many among the demonstrators wore the national colors of Brazil, yellow and green, associated in recent years with Bolsonaro supporters.
Brazil's President Luiz Inacio Lula da Silva walks in Planalto Palace after it was stormed by supporters of Jair Bolsonaro in Brasilia on Sunday.
Ibaneis Rocha, the governor of Brazil’s capital district, said more than 400 people involved in the demonstrations and breaches have been arrested.
He said authorities continued to work to restore order.
"The electoral cycle was marked by the use of public resources for campaigning and a sophisticated disinformation network," the nonprofit Carter Center said in November after having observed the presidential election.
"Most attacks targeted the Lula campaign," it sai
Lula accused the mob of taking advantage of the quiet Sunday as his administration was still moving into government.