Two people armed with handguns and wearing tactical military gear, balaclavas masking their face and the license plates on their cars covered, stood watch over a ballot drop box during early voting last week in Mesa, Arizona.

This scene, reported by the Maricopa County Elections Department on Friday, is one that some elections officials and law enforcement fear might spread as believers in Donald Trump's false claims that a second term as president was stolen from him through voter fraud amp up activity ahead of the Nov. 8 election. 

Other agitator election deniers are filming voters dropping off ballots, photographing their license plates and confronting them in parking lots outside early voting locations in Arizona and Michigan, according to Marcia Johnson-Blanco, who is overseeing election protection efforts for the Lawyers' Committee for Civil Rights Under Law.

At least three groups that make baseless claims of widespread voter fraud are encouraging untrained volunteers to engage in the effort. One effort, funded by Michael Flynn, Donald Trump's first national security adviser and a former Army general in Iraq 20 years ago, is specifically recruiting military veterans and police officers to monitor voting.