By David Wetzel New York (Knewz) — A Missouri man fatally shot his mother while they were arguing while putting groceries away, according to The Charlotte Observer. Police arrested a Missouri man, Tony Martin Jr., who they say was carrying a gun around their home on Sept. 21, before the shooting, according to a St. Louis Police Department report obtained by The Charlotte Observer. According to a probable cause statement from police, Christy Martin, the victim, at one point during the argument touched her son’s arm in an attempt to get him to turn around. According to The Charlotte Observer, Ma…