On Facebook and LinkedIn, David Jewberg presented himself as a Senior Russian Analyst for the U.S. Department of Defense who publicly advocated for a stronger American stance against the Kremlin.

But according to a new investigation by Bellingcat, a blog about Eastern Europe, Jewberg was an elaborate hoax character, likely created by Dan Rapoport, a Russian financier with connections to both Putin adversaries and the Trump family.

After he appeared online in 2015, the Jewberg character was heralded by the Russian opposition community as an anti-Putin thought leader in the U.S. military. He was quoted in the Russian media. An open letter bearing his signature went viral when he called on Facebook’s executives to fight pro-Kremlin bias among the site’s moderators, and Jewberg later announced that he had been included on a conference call with high-level Facebook staffers to discuss the issue (though Facebook did not respond to a question from The Outline about whether the conference call had actually taken place).

In November 2016, Jewberg announced his resignation from the Pentagon on Facebook, calling president-elect Donald Trump “everything I despised.”

But the State Department and Department of Defense both told Bellingcat that they’d never employed someone by the name of David Jewberg. “Jewberg” is not a common surname, and sometimes appears online in anti-semitic contexts.

Jewberg’s online persona was connected in various ways to Rapoport’s. On Facebook, for instance, Rapoport called Jewberg a “friend and brother.” Photos of Jewberg appear to show one of Rapoport’s college friends.

Another of Rapoport’s Facebook friends, David Satter, who had also interacted with Jewberg on Facebook, confirmed to Bellingcat that Jewberg was Rapoport’s “nom de plume.” Rapoport denied operating the Jewberg persona to Bellingcat, and did not respond to questions from The Outline.

Rapoport, who was born in Russia but has lived in the United States for many years, is an outspoken Putin critic. He also has an oblique connection to the Trump family: last year, he sold the D.C. house where Ivanka Trump and Jared Kushner now live —  though it’s not clear whether he sold it to the couple or whether they’re renting it from a different new owner.

It’s not certain, according to a number of experts Bellingcat spoke to, what the Jewberg persona was supposed to accomplish. One compared it to something that might be created by the “troll factory” Russia used to disrupt the United States’ 2016 presidential election.