Senate Democrats are demanding the Government Accountability Office (GAO) launch an inquiry into the costs of President Donald Trump‘s Fourth of July event in Washington, D.C. and into whether or not it adhered to legal restrictions.

Democratic Sens. Patrick Leahy (D-Vermont), Tom Udall (D-New Mexico) and Chris Van Hollen (D-Maryland) wrote a letter to GAO Comptroller General Gene Dodaro stating they are “concerned by the impacts and the precedent of diverting limited Federal resources” for the Independence Day celebration.

“Further, we are troubled by reports that preferential access to the National Mall was organized by political entities such as the Republican National Committee, which furthers the appearance that taxpayer funds were used to accomplish political objectives,” the trio of lawmakers said in the letter.

The National Park Service had redirected $2.5 million from its total budget in order to pay for the “Salute to America” celebration at the National Mall in Washington, which featured a military parade, fireworks and a long address from Trump. The newspaper also estimated that the military flyovers held at the event could ultimately cost more than $2 million, and cited a Pentagon official who said at least half of that sum would be incurred by the military.

After the event was held, Trump angrily blasted the liberal media on Twitter for not reporting on what he viewed as a large crowd of attendees at the celebration.

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