Raleigh, N.C. — A state investigation into Gov. Beverly Perdue's campaign finances is close to wrapping up, and Wake County District Attorney Colon Willoughby said Thursday that he expects it to result in more criminal charges.

The State Board of Elections fined the governor's campaign $30,000 a year ago for not reporting dozens of campaign flights aboard donors' planes during the 2004 and 2008 elections until late 2009.

Willoughby reviewed the information from the elections board's investigation and last fall asked the State Bureau of Investigation to look into the matter further to help him determine whether any criminal charges were warranted.

In February, a Wake County grand jury indicted Robert Lee Caldwell of Morganton, a Perdue political contributor, on one count of felony obstruction of justice.

The indictment alleged that Caldwell secretly paid for a plane to fly Perdue to a campaign stop and had another man report it as an in-kind donation.

Perdue has acknowledged that her campaign made mistakes reporting flights, but she has insisted that there was no criminal intent.

Willoughby said nothing has been brought up in the investigation to implicate Perdue or any other elected official in any wrongdoing.

He wouldn't signal who could be charged in the investigation or what the charges might be. Any felony charges would be run through a Wake County grand jury, but he said that probably wouldn't happen next week, when the grand jury next meets.

Perdue said last fall that federal investigators also were looking into her campaign finances. It's unclear whether that probe is ongoing.

“We have no information beyond what the district attorney has said today. We need to give him time to complete his investigation and, at that point, I’m sure he will make an announcement regarding whatever actions he decides to take," Perdue committee consultant Marc Farinella said in a statement. "The Perdue campaign committee remains committed to assisting his investigation in any way it can. Aside from that, there is little to say except that we are pleased that the district attorney has made the point that he found nothing to suggest that the governor has been involved in any type of wrongdoing.”