In a bombshell hearing, Burgos said Nicolás Petro revealed that some of the money was used for his personal benefit and to unlawfully increase his wealth. The rest, prosecutors said, was destined for Gustavo Petro’s presidential campaign.

According to Burgos, Nicolás Petro agreed to turn in more evidence and to resign from his political post, as well as to steer away from accepting any other political roles.

The revelations mark the most significant scandal yet in an already turbulent first year for Gustavo Petro, Colombia’s first leftist president. If proved true, the allegations could set the stage for a potential impeachment investigation — or even criminal investigation — into what the president himself knew about the campaign money.

President Petro, speaking Thursday at an event in northern Colombia, denied any connection to the allegations.

“The president of the republic has never asked any of his sons or daughters to commit a crime, neither to win, nor to finance campaigns, nor for anything that has to do with power,” Petro told a crowd in the Sucre region. “My sons and daughters have been free. They may make mistakes like every human being. They’ll walk different paths from mine, maybe, but from their father you will never expect that. It has not happened and it will not happen.”

An attorney representing Nicolás Petro did not immediately provide comment Thursday evening, saying he was still in court.

The latest details in the case now leave the struggling president further weakened in front of a divided congress that could be tasked with investigating him, said Yann Basset, a political science professor at Colombia’s Rosario University.

“Even without this scandal it was very complicated, because he did not have the majority in the congress and he has not wanted to negotiate with political parties,” Basset said. “Now the government’s only agenda is basically to survive.”

Prosecutors will start a new probe into the illicit money that allegedly ended up in Gustavo Petro’s presidential campaign, Burgos said, because some of it was not reported to electoral authorities.

Nicolás Petro’s former wife, Daysuris Vásquez, was also charged with money laundering and taken into custody Saturday, Colombia’s attorney general said in a news release.

Their arrests come months after Vásquez, who separated from Nicolás Petro following his alleged affair with one of her former friends, accused him in a Semana magazine interview in March of using money donated to his father’s presidential campaign to support a lavish lifestyle. Gustavo Petro was unaware of his son’s actions, according to Vásquez.

“The money never got to his [father’s] campaign,” Vásquez told Semana.

Back then, Nicolás Petro denied he had misused any money from the campaign in a statement issued after the Semana story was published, and said he would cooperate with authorities.

The arrest of the Colombian president’s son also comes weeks after leaked audio messages implicated the president’s chief of staff and his ambassador to Venezuela in possible campaign finance violations. Gustavo Petro fired both of them after Colombia’s attorney general launched a probe into the matter.

After the arrest of his son and Vásquez, the president said he would let the investigation run its course, further distancing himself from the matter.

“That one of my children has to go through jail hurts,” Gustavo Petro said Saturday in a statement. “As the president, I can assure the attorney general’s office that they have all the avenues on my end to proceed according to the law.”

Unlike regional neighbors such as Peru, where a series of presidents have recently been ousted, Colombia’s political system carves out a difficult path for impeaching a president. An impeachment trial must go through both chambers of congress and then to the Supreme Court.

Since its creation decades ago, the country’s congressional investigative committee has never impeached a president, said Ramiro Bejarano, a lawyer and law professor at Colombia’s University of the Andes.

Still, Bejarano said, Petro’s political power is diminishing each day.

“The only solution that I see for Petro to get out of this crisis is to call on all political parties and negotiate with them,” he said. “The dream of governing as one party on the left has been cut short.”