Updated at 1:10 p.m. ET

The Defense Department, reacting to armed citizens appearing in front of military recruiting offices around the country since last week's fatal shootings of five U.S. servicemen in Chattanooga, Tenn., has asked that "individuals not stand guard" on federal property.

"We take the safety of our service members, our DoD civilians, and the families who support them very seriously, and Secretary of Defense Ash Carter is currently reviewing recommendations from the services for making our installations and facilities safer — including our recruiting stations," Pentagon press secretary Peter Cook said in a statement.

"While we greatly appreciate the outpouring of support for our recruiters from the American public, we ask that individuals not stand guard at recruiting offices as it could adversely impact our mission, and potentially create unintended security risks," Cook said. "We continue to partner with and rely on first responders for the safety of the communities where our service members live and work."

The self-appointed armed guards began appearing in front of recruiting centers shortly after the July 16 shooting rampage by lone gunman Mohammod Youssuf Abdulazeez at Tennessee military sites that killed four U.S. Marines and a U.S. Navy sailor.

As we reported on Thursday, the U.S. Army Recruiting Command had issued a policy letter warning its soldiers to avoid vigilante guards and to report them to local law enforcement and the command.

Some of the self-appointed guards – who have appeared outside recruiting centers in Wisconsin, Georgia, Tennessee, Idaho, Washington, Texas, South Dakota and elsewhere — are affiliated with militia groups, according to Stars and Stripes.

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