Former New Orleans Mayor Ray Nagin, a Democrat, is under federal investigation relating to the awarding of city contracts in exchange for favors or items of cash value while he was in office.

Sources tell Reuters that multiple individuals linked to Nagin, including those who worked in his administration, are now cooperating with federal investigators.

Nagin, on a trip to Minnesota today, was asked about the investigation. He insisted that he’s innocent but says he’s “starting to worry” that, in his view, “truth and justice” won’t prevail.