Brazil’s President Luiz Inácio “Lula” da Silva has joined a growing chorus of accusations against the country’s security forces, as questions mounted on how protesters were able to breach government buildings and wreak havoc inside over the weekend.

“The Brasilia police neglected [the attack threat], Brasilia’s intelligence neglected it,” Lula said during a meeting with governors on Monday.

“It is easy to see in the footage the police officers talking to the attackers. There was an explicit connivance of the police with the demonstrators,” he said. He also vowed to find out who financed the protesters.

Protesters supporting the far-right former President Jair Bolsonaro besieged the Supreme Court, presidential palace and Congress on Sunday, calling for the military to intervene and oust the leftist hero Lula da Silva, who returned to power after a 12-year hiatus following a slim run-off victory over Bolsonaro last October.

Footage shared of the attack appeared to show forces stand by and watch protesters march into government buildings.

CNN has reached out to Brasilia’s Federal District Military Police and Armed Forces for comment.

Brazilian officials have been racing to catch the perpetrators while looking into claims that security and intelligence authorities colluded with the protesters.

Paulo Pimenta, Brazil’s presidential communications minister, told reporters on Monday that the events on Sunday could not have transpired “without some level of facilitation.”

He noted that the main doors to Congress and the presidential palace weren’t broken, suggesting some form of collusion.

“The main door was not broken, so people walked in through the door. In the Congress building, the door was not damaged either. At the Supreme Court, you can see the door was destroyed – which clearly leads me to believe that investigations will mostly likely indicate that they may have come in here [the Planalto presidential palace] and in the National Congress through the main door,” he said according to Brazilian state news Agencia Brasil.

On Sunday, Brazilian Supreme Court judge Alexandre de Moraes temporarily removed Ibaneis Rocha, Brazil’s Federal District governor, from his post for three months.

Rocha, a Bolsonaro ally, has been serving as the governor of the Federal District, which includes the capital Brasilia.

Prior to his removal, Rocha on Sunday fired Anderson Torres, the former head of security for the Federal District.

Torres, who was the former justice minister in Bolsonaro’s government, called the scenes “regrettable,” adding he had ordered “immediate steps to restore order in the center of Brasília.

He later claimed to be on vacation in Orlando, Florida with his family and said he had not been in contact with Bolsonaro, according to Brazilian daily Folha de Sao Paulo.

Bolsonaro on Monday tweeted a photo of himself from a hospital bed in Orlando – saying he was receiving treatment for complications relating to an old stab wound – as several US lawmakers called for his removal from the country following the attacks by his supporters.