Oath Keepers descend on Ferguson
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Another fragile night of unrest in Ferguson, Missouri, was compounded by the unexpected appearance of heavily armed men belonging to a controversial organization known as the Oath Keepers.

Described as a "fiercely anti-government, militaristic group” by the Southern Poverty Law Center, the Oath Keepers claim 30,000 members among their ranks, all led by group founder Stewart Rhodes, a former U.S. Army paratrooper who worked as an aide to former Rep. Ron Paul (R-Texas).

Rhodes was reportedly not in attendance late Monday as a handful of Oath Keepers descended on the scene of protests marking a year since the fatal shooting of Michael Brown by officer Darren Wilson.

At least five individuals were spotted wearing bulletproof vests and openly carrying "assault weapons,” St. Louis Public Radio reported. They claimed to be providing protection for an InfoWars journalist covering the event.

Protesters attempted to distance themselves from the Oath Keepers and push them back, while St. Louis County Police Chief Jon Belmar referred to their presence as "both unnecessary and inflammatory.”

Some 23 people were arrested during Monday night’s protests; no Oath Keepers are believed to be among them.

According to NBC News, Rhodes has a history of inflammatory statements, including referring to Hillary ClintonHillary Diane Rodham ClintonBloomberg called Warren 'scary,' knocked Obama's first term in leaked audio Trump trails Democratic challengers among Catholic voters: poll Sanders under fire from Democrats over praise for Castro regime MORE as “Hitlery,” and calling for Sen. John McCainJohn Sidney McCainSanders says idea he can't work with Republicans is 'total nonsense' GOP casts Sanders as 2020 boogeyman Overnight Defense: GOP lawmaker takes unannounced trip to Syria | Taliban leader pens New York Times op-ed on peace talks | Cheney blasts paper for publishing op-ed MORE (R-Ariz.) to be executed for treason.

In the aftermath of last month’s shooting in Chattanooga, which claimed the lives of four Marines and a Navy sailor, Rhodes urged Oath Keepers to take up arms.

"Go armed, at all times, as free men and women, and be ready to do sudden battle, anywhere, anytime, and with utter recklessness,” Rhodes wrote on the Oath Keepers website, NBC News reported. "That IS the price of freedom.”

Missouri law permits gun owners with a license to carry concealed weapons to openly carry so long as their weapons aren't displayed in an "angry or threatening manner."