The border militia leader arrested over the weekend first came to the FBI’s attention in October 2017, according to a court document unsealed Monday, after the bureau learned that he “allegedly made the statement that [his militia] the United Constitutional Patriots were training to assassinate George Soros, Hillary Clinton, and Barack Obama, because of these individuals’ support of Antifa.”

The filing makes clear that militia leader Larry Mitchell Hopkins was on the radar of law enforcement long before the ACLU of New Mexico last week flagged videos of armed members of the United Constitutional Patriots members “arresting” migrants and falsely identifying themselves as federal agents.

After the civil liberties group called on New Mexico’s governor and attorney general to investigate the militia’s activities, Hopkins was arrested for possessing a firearm as a felon, which is itself a felony.

In a court filing Monday, FBI special agent David S. Gabriel said FBI agents “immediately observed approximately 10 firearms” upon entering what Hopkins told them was his “office,” inside his home in northern New Mexico in November 2017. Per the filing, Hopkins told the officers the guns belonged to his “common law wife.”

Hopkins has prior convictions for felony possession of a firearm and felony impersonation of a peace officer.

Hopkins’ lawyer, former conservative radio host Kelly O’Connell, questioned why his client was being arrested for the 2017 incident over a year later in an interview with The New York Times.

“Why now?” O’Connell said, suggesting that the FBI was only acting in response to pressure from Democratic officials.

O’Connell also denied that United Constitutional Patriots trained to carry out assassinations, telling the Times, “My client told me that is not true.” He said Hopkins planned to plead not guilty.

Read the filing here, via HuffPost’s Ryan J. Reilly.