The conspiracy theory that President Donald Trump pushed on Monday that a plane "almost completely loaded with thugs" was set to disrupt the Republican National Convention was almost identical to a rumor that went viral on Facebook three months ago.
In an interview with Fox News host Laura Ingraham, Trump claimed that "we had somebody get on a plane from a certain city this weekend, and in the plane it was almost completely loaded with thugs, wearing these dark uniforms, black uniforms, with gear and this and that."
He then claimed the matter was "under investigation right now."
There is no evidence of any such flight. When Ingraham asked for more information about the flight, the president said, "I'll tell you sometime." He then alleged the people were heading to Washington to disrupt the RNC.
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Before mentioning the dark uniformed men who allegedly boarded a plane, Trump claimed that there are "people that are in the dark shadows" and "people that you haven't heard of" controlling Democratic nominee Joe Biden.
Ingraham pressed the president for more details and said it sounded like he was alleging a conspiracy.
"They're people that are on the streets. They're people that are controlling the streets," Trump said.
The claim about a flight matches a viral Facebook post from June 1 that falsely claimed, "At least a dozen males got off the plane in Boise from Seattle, dressed head to toe in black." The post, by an Emmett, Idaho man, warned residents to "Be ready for attacks downtown and residential areas," and claimed one passenger had "a tattoo that said Antifa America on his arm."
That post was shared over 3,000 times on Facebook, and other pages from Idaho quickly added their own spin to it, like the Idaho branch of the far-right militia group 3 Percenters.
One post claimed that "Antifa has sent a plane load of their people" and that the Payette County Sheriff's Office confirmed it. Within days, that version of the rumor picked up enough steam in Idaho Facebook groups that the Payette County Sheriff's Office had to release a statement insisting that the viral rumor was "false information."
Rumors of marauding bands of Antifa supporters have plagued local Facebook groups, chain emails and forwarded text messages since mid-May. One of the most viral rumors on an Antifa invasion into the suburbs was taken down after Twitter said it was created by a troll account with ties to white nationalists.
Some armed Americans took to town squares in several towns to fight off fictitious busloads of Antifa in June, spurred by false rumors on Facebook pages. Seven days after the original Idaho rumor went viral on Facebook, armed men stood guard over protests in Missoula, Montana, worried about the planeloads of Antifa supporters.