The acting chief executive of the Clinton Foundation admitted on Sunday that the charity had made mistakes on its tax returns regarding its list of donors, Reuters reports. The admission comes after a Reuters review of the foundation’s taxes.

“Yes, we made mistakes, as many organizations of our size do, but we are acting quickly to remedy them, and have taken steps to ensure they don’t happen in the future,” acting Chief Executive Officer Maura Pally said in a statement on Sunday.

Last week, after Reuters found errors in the way the charity reported donations from governments, the Clinton Foundation said that it would refile at least five annual tax returns. On Sunday, Pally said that the foundation accurately reported its total revenue but that government grants were combined with other donations.

In 2013, the foundation took in more than $140 million in grants and pledges, the New York Post reports, but spent just $9 million on direct aid. Charity Navigator, which rates non-profits, recently put the foundation on its watch list.

The New York Times reported last week that the Clinton Foundation received—in the most convoluted and financially obscure ways possible—money from “a Canadian company with uranium-mining stakes stretching from Central Asia to the American West” known as Uranium One. While Hillary Clinton was still secretary-of-state, Uranium One sought the State Department’s approval of a Russian takeover. (According to the Times, the deal required State Department approval because uranium is a strategic asset.)

From the Times:

As the Russians gradually assumed control of Uranium One in three separate transactions from 2009 to 2013, Canadian records show, a flow of cash made its way to the Clinton Foundation. Uranium One’s chairman used his family foundation to make four donations totaling $2.35 million. Those contributions were not publicly disclosed by the Clintons, despite an agreement Mrs. Clinton had struck with the Obama White House to publicly identify all donors. Other people with ties to the company made donations as well.

And shortly after the Russians announced their intention to acquire a majority stake in Uranium One, Mr. Clinton received $500,000 for a Moscow speech from a Russian investment bank with links to the Kremlin that was promoting Uranium One stock.

“It seems,” Bill Allison, a senior fellow at the Sunlight Foundation, told the Post, “like the Clinton Foundation operates as a slush fund for the Clintons.”

Photo credit: AP Images. Contact the author of this post: brendan.oconnor@gawker.com.