Federal Agents Join School Bus Threat Probe in Ga. Police in an Atlanta suburb have enlisted the help of federal agents to examine a rifle dropped by a man who was seen aiming at a school bus and left behind a notebook with bus numbers. Clayton County police Officer Phong Nguyen says the Bureau of Alcohol, Tobacco, Firearms and Explosives will try to obtain leads from the weapon, a Marlin .22-caliber rifle. The Atlanta Journal-Constitution (http://bit.ly/KgtbDk) reports that more than 50 officers spent Wednesday afternoon going door-to-door in the neighborhood where witnesses saw the man aiming at the bus Monday morning. The man fled when witnesses confronted him. Authorities say a neighbor chased him, but stopped when the man used a second gun and shot at him. Police recovered the rifle and a notebook filled with bus numbers. Information from: The Atlanta Journal-Constitution, http://www.ajc.com