Zül-Qarnau012fn Nantambu says he's the guy on video scuffling with Antonio Brown outside the Adin Ross boxing event in Miami ... and he claims Antonio went to grab a gun and shot at him.
Zül-Qarnau012fn tells TMZ ... AB squeezed off a couple shots during Friday night's incident, and there were kids around when the former NFL player pulled the trigger.

Video appears to show Antonio running through a crowd with a gun in his left hand, and you see him turn a corner and raise his arm before multiple gun shots ring out.