The Justice Department said four Georgia men arrested earlier this week and charged with plotting to buy explosives are part of a fringe militia group.

But just how many of those groups are active in Georgia is unclear.

The Southern Poverty Law Center said in a report earlier this year that there are as many as 34 anti-government extremist groups operating in Georgia. It identified four of those as militias.

The Anti-Defamation League also tracks fringe groups. Accounting for small splinter groups and individuals who consider themselves militia, ADL’s southeast regional director Bill Nigut said it’s unclear how many extremist militias or other anti-government groups operate in Georgia.

But he said law enforcement agencies are worried about them.

“What law enforcement wants from us, right now, is training in dealing with anti-government activists, better know these days as sovereign citizens,” Nigut said.

“And the reason law enforcement has been calling on us to do a lot of training on those organizations is [because] they are the most dangerous to law enforcement. They are willing to fight and kill law enforcement officers,” Nigut said.

The Georgia Bureau of Investigation’s John Bankhead said calling them “groups” is the wrong term. It’s really more about individuals.

“It’s kind of a fine line with respect to people who have anti-government sentiments, which they can legally have and they have a right to have,” he said. “It’s just when they step over the line and get involved in criminal activities where law enforcement has to take action.”

Nigut said three of the four men arrested this week were not on the Anti-Defamation League’s radar and seem to have no history of extremist actions.

Tags: Anti-defamation league, Southern Poverty Law Center, Militia movement, Georgia militias, extremist groups