Colombian prosecutors opened an investigation into the financing of Gustavo Petro’s 2022 presidential campaign, following a scandal that has already caused two top aides to step down.

Prosecutors will look to determine whether the campaign broke the law by accepting money from prohibited sources, or by violating spending limits, according to a statement from the Attorney General’s office.

The investigation comes after Semana magazine published leaked audios from Petro’s former campaign chief, Armando Benedetti, hinting at a breach of financing rules during the election. Both Benedetti and Petro’s cabinet chief stepped down earlier this month.

The Presidency didn’t immediately reply to a request for comment.

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