Michael Zaremski of Green, formerly a Hackettstown EMT, pointed a gun at the back of the woman's head and said: "Guess if it's loaded or not," NJ.com reports.
Zaremski, 25 -- found to be in possession of an arsenal of weapons -- had an interest in committing a mass shooting at a hospital and was obsessed with Hitler, the woman told police.
He also forced the woman into wearing an Nazi SS hat so he could took her picture, which he later posted to a bogus Instagram account in her name and followed her Jewish employer, NJ.com says.
The woman made a harassment complaint last June, ultimately leading to Zaremski's arrest.
Zaremski was armed with a loaded 9mm handgun labeled "Hackettstown EMS" inside of his EMS jacket, which he carried while working, police said.
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