A senior law enforcement official told ABC News Wednesday that three men charged with federal firearms violations earlier this week have alleged ties to a white supremacist extremist group and were found to be in possession of what is being investigated as a possible list of targets.
Garza declined ABC News' request for further comment, and the Justice Department declined to comment when asked about any connection between the 'list' and the arrests announced Tuesday. The senior official who spoke to ABC News also declined to further characterize the list.
The three men - Liam Collins, Jordan Duncan and Paul Kryscuk -- are facing gun trafficking charges. According to a report from Newsweek last year, prior to officially joining the Marines, Collins was a frequent poster on a message board associated with white supremacists and neo-Nazis.
For the moment, prosecutors have kept further details of the case under seal. Listed attorneys for all three men did not immediately respond to ABC News' request for comment.
The Marine Corps confirmed to ABC News that both Collins and Duncan were former Marines former stationed at Camp Lejeune in North Carolina and that Collins was discharged prematurely last month.
"The Marine Corps will continue to assist the investigating authorities in any way we can," the Marine Corps said in a statement. "The serious allegations are not a reflection of the Marine Corps, do not reflect the oath every Marine takes to support and defend the constitution, and do not align with our core values of honor, courage, and commitment."
In a follow-up statement Wednesday, U.S. Marine Corps spokesman Capt. Joe Butterfield confirmed Collings was investigated "on allegations of white supremacist activity" but that "actions resulting from that investigation are administrative in nature and therefore not releasable."
FBI Director Christopher Wray recently warned that white supremacy-motivated extremists make up the most prevalent type of domestic terrorism threat the bureau is observing around the U.S.
"Within the domestic terrorism bucket, the category as a whole, racially motivated violent extremism is, I think, the biggest bucket within that larger group. And within the racially motivated violent extremist bucket, people subscribing to some kind of white supremacist-type ideology is certainly the biggest chunk of that," Wray said.
“Lately we've been having about 1,000 domestic terrorism cases each year. It is higher this year," Wray added. "I know we’ve had about 120 arrests for domestic terrorism this year."
In February of this year, the Justice Department announced a series of nationwide arrests of members of the group Atomwaffen, as the FBI steps up its policing of neo-Nazi groups in the U.S.
John Denton, the former leader of Atomwaffen, was arrested in Virginia for his alleged role in coordinating several "swatting events" that targeted a university, a Baptist church and a news organization, among others.
According to a criminal affidavit, Denton allegedly conspired with others to make prank calls through the encrypted app Mumble in order to trick law enforcement dispatchers into believing Denton's intended targets were in imminent danger of death or causing harm to others, often generating significant emergency responses to unwitting individuals or groups.