In a press conference on Friday, authorities confirmed that the explosive devices sent to prominent Democrats and Trump critics were "not hoax devices"

Donald Trump Jr. liked a tweet that falsely claimed that the pipe bombs sent to numerous prominent Democrats and Trump critics this week had been fake, and were only sent to engender sympathy for the political party opposing his father.

“BREAKING: WHITE POWDER IN BOMBS NOT BIOLOGICAL OR DANGEROUS. LIKELY BABY POWDER,” began the misleading tweet from Twitter account USA News, which has no affiliation with news outlet USA Today.

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The tweet went on to falsely claim that the “FAKE BOMBS” were “MADE TO SCARE AND PICK UP BLUE SYMPATHY VOTE” in the upcoming midterm elections.

FBI Director Chris Wray confirmed on Friday that while authorities “are still analyzing the devices in our laboratory, these are not hoax devices.”

Trump Jr., 40, has since appeared to have un-liked the tweet, which supports a message spread by fringe right-wing media personalities, the Daily Beast noted in its coverage of Trump Jr.’s like.

The tweet included a Fox News video clip from FBI Assistant Director William Sweeney’s press conference on Thursday. During the media appearance, Sweeney said that a white powder that had been found in some of the packages was “not biological,” The Hill reported.

The clip cut out shortly after Sweeney’s remarks, as a Fox News host said that they had been told by authorities that talcum powder is sometimes used to “amplify the fear factor.” Authorities have yet to clarify what kind of white powder was found in the envelopes.

Confirming its political allegiance, the Twitter account’s bio reads: “Donald Trump has been the greatest President we’ve had in 100 years! Media Lies! Twitter censors us. #DrainTheSwamp #BuildTheWall #ConfirmKavanaughNow.”

In a press conference on Friday, authorities confirmed that Cesar Sayoc of Aventura, Florida, had been arrested in connection with the attempted attacks. Authorities said they were able to confirm his identity from a fingerprint found on a package sent to California Rep. Maxine Waters.

FBI Director Wray also confirmed that while authorities “are still analyzing the devices in our laboratory, these are not hoax devices.”

“Each device consisted of roughly of six inches of PVC pipe, a small clock, battery, and energetic material, potential explosives and material that give off heat and energy through a reaction to heat, shock, or friction,” he added.

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While authorities are not yet commenting on the motivation behind the attempted attacks, the New York Times reported that Sayoc is a 56-year-old registered Republican from Florida. On Friday morning, police were seen surrounding a white van decorated with pro-Trump stickers, which was later hauled away underneath a tarp, although according to the outlet, it is not clear whether the van belonged to Sayoc.

Sayoc has been arrested numerous times in the past, including for a bomb threat in 2002, for which he pleaded guilty, according to the Washington Post.

Image zoom Cesar Sayoc AP/REX/Shutterstock

During the press conference, United States Attorney General Jeff Sessions revealed that Sayoc has been charged with “five federal crimes, including interstate transportation of an explosive, illegal mailing of explosives, threats against former presidents and certain other persons, threatening interstate communications, and assaulting current and former federal officers.”

Sayoc faces up to 58 years in prison for those charges. It was not immediately clear if Sayoc has a lawyer who can comment on his behalf.

Shortly before news of Sayoc’s arrest was released on Friday, authorities recovered two additional suspicious packages. One was sent to addressed to Democratic New Jersey Sen. Corey Booker, while a second was addressed to James Clapper, the former director of national intelligence.