Unarmed Citizen Body-Slams Armed Robber

…Lee says he saw the man reaching for his waistband and believed he had a gun -- so he slammed the guy down to the ground.

Turns out, Lee's instincts were right ... the guy did have a gun -- which was quickly recovered by one of the cooks.

Cops were called to the scene and arrested 18-year-old Arnez Harper on a count of felony aggravated unlawful use of a weapon.

"He (my husband) used to be a bouncer when he was a young lad," Victoria says of her hubby ... "I think that guy crossed the wrong person." …