The FBI is investigating anti-fascist activists for an alleged plot to buy guns from a Mexican cartel in order to “stage an armed rebellion” at the southern border, according to an unclassified document obtained by The Chicago Tribune.

The FBI document, from December of 2018, warns of militant antifa activists planning to “disrupt security operations” at the U.S.-Mexico border. The group allegedly planned to buy guns from a Mexican cartel associate known as Cobra Commander, in order to “stage an armed rebellion at the border.”

The source who provided it to the San Diego Tribune asked the outlet not to publish the six-page document because the investigation is ongoing, and the outlet cited two additional law enforcement officials who confirmed the news. The FBI has warned dozens of law enforcement agencies in both Mexico and the United States of the alleged plot.

Two of the men named in the report told the San Diego Tribune the allegations are absurd.

“It doesn’t make any sense that someone from the United States would purchase guns in Mexico,” Ivan Reibeling, the man known as Cobra Commander, told the outlet. “And the Hondurans certainly didn’t bring money to buy guns. It doesn’t make any sense; in fact it’s extremely absurd to say the Hondurans wanted to attack the United States at the border.

The FBI sent the report marked “priority” to agencies including the Department of Homeland Security, U.S. Customs and Border Protection, the CIA and the National Security Administration.

Antifa is known for using violent means, including in protests against peaceful conservative speakers, free speech advocates and even journalists. The well-documented instances of violence include a protester repeatedly punching a man in the face, throwing water bottles and launching fireworks at police officers and starting fires on a college campus with Molotov cocktails. The Daily Caller News Foundation’s reporting led to the arrest of an Antifa leader who stands accused of accosting and assaulting two Marines in Philadelphia. (RELATED: Five Times The Establishment Media Excused Antifa Violence)

Former Vice President Joe Biden launched his campaign for president by praising the group. He referred to a group of protesters who gathered in Charlottesville, VA, and violently confronted white nationalists “a courageous group of Americans.”

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