Brazilian President Michel Temer has ordered the armed forces to patrol Brasilia for a week, following protests that called for the end of his government and immediate elections for a new President.
A series of clashes took place between tens of thousands of protestors and the policemen.
Protestors set on fire a ministry building and the police used tear gas and pepper spray against the crowd, Xinhua news agency reported.
It was the country's latest episode in the escalation of violence and political chaos that started last week when reports said Temer was caught on tape engaging in obstruction of justice and endorsing bribes to a witness in a corruption case.
The tape was recorded by a businessman with whom Temer had talked in his official residence late at night in a secret meeting in March.
In the 40 - minute - long conversation, released on Friday, Temer approved bribes paid to Eduardo Cunha, former lower house Speaker and Temer's main ally in the impeachment of former President Dilma Rousseff.
The businessman Joesley Batista, who is head of meatpacker JBS, talked to Temer about his corrupting judges and prosecutors while the President showed no reproach.
The Supreme Court has already opened an investigation into the President over allegations of corruption and obstructing justice.
Temer's defence was that the recordings were doctored despite his really having engaged in an unscheduled meeting with Batista, but it was not very convincing to the public, nor to Congress.
Calls for his resignation or impeachment continued, but Temer remained resolute to see his term through, even saying that he will not resign unless he is forced out of office.
Brazilian law states that when a President resigns or is impeached in the final two years of the term, indirect elections must be held within 90 days.
However, many Brazilians believe direct elections are the only way to ensure political stability in the country and give legitimacy to the presidency, since the Brazilian Congress is not very popular among them right now.
Earlier on Wednesday, more than 35, 000 people who defend direct elections gathered in Brasilia for a protest demanding that the President step down.
Amid the confusion, protestors damaged some areas in the ministries' lane, the main avenue in Brasilia, where ministry buildings are located side by side.
Offices of five ministries were damaged and a fire was started, but was quickly put out by the fire department.
At least 49 people were injured in scuffles between policemen and protestors.
To contain the chaos, Temer ordered the army on the streets.
Meanwhile, the President lost two advisors - - one quit and the other was arrested for corruption.
On Saturday, the Brazilian Socialist Party (PSB) announced it was pulling out of the ruling coalition and seeking Temer's ouster.