President Donald Trump took to Twitter on Sunday to call for an investigation into “who paid for the small organized rallies yesterday” – referring to the anti-Trump Tax Day March held Saturday in Washington and at least 60 other locations.

Trump may have missed a Breitbart News exclusive investigative article penned by this reporter on February 16 titled, “Soros Groups Behind Massive Anti-Trump Tax Day Protest Plot.”

While there is no immediate information on who directly bankrolled this specific protest movement, Breitbart News found that most of the listed partners and support organizers of the march are openly financed by George Soros or have close links to Soros financing.

Someone should look into who paid for the small organized rallies yesterday. The election is over! — Donald J. Trump (@realDonaldTrump) April 16, 2017

Trump’s tweet itself received widespread news media coverage. However, scores of major news media articles reviewed by this reporter failed to document the Soros ties to the tax march.

“Trump calls for investigation into Tax Day protesters, tweets ‘election is over!’” reads a CNBC.com article.

After noting an initial Trump tweet on the difficulty of a Republican winning the Electoral College, NBC News reported:

The president then followed up by repeating an unsubstantiated claim he’s made before that some of the protesters against him were “paid,” an allegation that became popular in some right-wing circles in the build up to the 2016 presidential election, before noting that the election was “over.”

“Trump’s Tweets Give Tax Day Marchers at Least Part of What They Wanted,” noted the headline in a Vanity Fair report. The article’s sub-headline reads: “He may never release his tax returns, but thousands of marchers around the country got their message heard.”

The website for the Tax Day march claims that its mission is to get Trump to release his tax returns and more.

The site reads:

President Trump needs to be straight with the American people. To whom does he owe favors? Who are his policies really intended to benefit? Who will he put first? Working families are struggling to make ends meet, but we pay our fair share in taxes – does Donald Trump pay any at all?

A query about protest financing sent to the email address for press inquiries listed on the Tax Day March website was not answered as of this writing.

Organizers of the March claim to be “ordinary Americans, community organizers, advocates, and people from all walks of life and all backgrounds joining together to raise our voices and send a bold message to this administration.”

In February, Breitbart News documented a section of the Tax Day March website titled, “Who is organizing it?” The website for the Tax March listed the following eight groups, six of which are either funded by Soros or tied to Soros financing.

The Tax March is grateful to have the support of the following organizations: American Federation of Teachers, Americans for Tax Fairness , Center for Popular Democracy, Indivisible Project, MoveOn.Org, Our Revolution, and The Working Families Party.

Americans for Tax Fairness is the recipient of a grant from Soros’s Open Society Foundations’ U.S. Programs.

MoveOn.Org is financed by Soros.

The American Federation of Teachers’ Educational Foundation, the nonprofit arm of the American Federation of Teachers , was financed by the Strategic Opportunities Fund of Soros’s Open Society Foundations, leaked Open Society documents show.

The Center for Popular Democracy is led by Soros-tied activists . In 2013, Marbre Stahly, a policy advocate at the Center, became a Soros Justice Fellow, which comes with a stipend of $58,700-$110,250 to fund full-time activism projects that last between 12-18 months. The Center was listed as Stahly’s “host” for the grant.

According to her bio , the Center’s research analyst, Maggie Corser, “spent four years at the Open Society Foundations where she conducted research on the future of work, conservative political infrastructure, and a range of economic justice issues.”

Shawn Sebastian, the Center’s field director for its Fed Up Campaign, was a fellow at the so called Anti-Corruption Unit of the Open Society Foundations’ Justice Initiative.

Another Tax March organizer is the recently-formed Indivisible Project. In February, Breitbart News extensively reported that Indivisible leaders are openly associated with groups financed by Soros.

Leaders of January’s Women’s March coalition reportedly helped to organize the Tax March, which USA Today described as a “sequel” to the massive march. Buzzfeed took note of the comparison to the Women’s March in a piece titled, “Progressives Want Tax Day To Be The Next Women’s March Protest.”

Soros reportedly has ties to more than 50 “partners” of the Women’s March. This journalist first reported on the march leaders’ close associations with Soros.

Since Breitbart’s probe in February, numerous other Soros-financed groups joined the march and are listed as “partners” on the group’s website. The Soros-funded “partners” include Demos and Public Citizen, among others.

Meanwhile, at the protest itself, Rep. Maxine Waters (D-Calif.) called for Trump to be impeached.

“I don’t respect this president. I don’t trust this president. He’s not working in the best interests of the American people,” complained Waters.

“I will fight every day until he is impeached,” she stated.

Aaron Klein is Breitbart’s Jerusalem bureau chief and senior investigative reporter. He is a New York Times bestselling author and hosts the popular weekend talk radio program, “Aaron Klein Investigative Radio.” Follow him on Twitter @AaronKleinShow. Follow him on Facebook.

With research by Joshua Klein.