JEFFERSON CITY, Mo. (AP) — A government watchdog group has filed an IRS complaint against a group that donated millions of dollars to a PAC that helped Eric Greitens’ Missouri gubernatorial campaign.

Citizens for Responsibility and Ethics in Washington filed the complaint this past week against Freedom Frontier. The group alleges the nonprofit violated its tax-exempt status by contributing more than half of its total spending to political organizations.

An Associated Press request for comment to Freedom Frontier was not immediately returned Monday.

IRS filings show the nonprofit spent about $5.9 million in 2016. It gave close to $4.4 million to LG PAC, which ran attack ads against Greitens’ opponents in the 2016 primary. As a nonprofit, it’s required to disclose its donors.

Greitens won election but resigned amid personal and political scandal in June.