In 2009 Alwan applied as a refugee and was allowed to move to Bowling Green, where he quit a job he briefly held and moved into public housing on Gordon Ave., across the street from a school bus stop, and collected public assistance payouts, federal officials told ABC News.
"How do you have somebody that we now know was a known actor in terrorism overseas, how does that person get into the United States? How do they get into our community?" wondered Bowling Green Police Chief Doug Hawkins, whose department assisted the FBI.
Department of Homeland Security spokesperson Peter Boogaard said in a statement that the U.S. government "continually improves and expands its procedures for vetting immigrants, refugees and visa applicants, and today [the] vetting process considers a far broader range of information than it did in past years."
"Our procedures continue to check applicants' names and fingerprints against records of individuals known to be security threats, including the terrorist watchlist, or of law enforcement concern... These checks are vital to advancing the U.S. government's twin goal of protecting the world's most vulnerable persons while ensuring U.S. national security and public safety," the statement said.
Last year, a Department of Homeland Security senior intelligence official testified in a House hearing that Alwan and Hammadi's names and fingerprints were checked by the FBI, DHS and the Defense Department during the vetting process in 2009 and "came in clean."
After the FBI received the intelligence tip later that year, a sting operation in Kentucky was mounted to bait Alwan with a scheme hatched by an undercover operative recruited by the FBI, who offered Alwan the opportunity to ship heavy arms to al Qaeda in Iraq. The FBI wanted to know if Alwan was part of a local terror cell -- a fear that grew when he tapped a relative also living in Bowling Green, Hammadi, to help out.
The FBI secretly taped Alwan bragging to the informant that he'd built a dozen or more bombs in Iraq and used a sniper rifle to kill American soldiers in the Bayji area north of Baghdad.
"He said that he had them 'for lunch and dinner,'" recalled FBI Louisville Supervisory Special Agent Tim Beam, "meaning that he had killed them."
Alwan even sketched out IED designs, which the FBI provided to ABC News, that U.S. bomb experts had quickly determined clearly demonstrated his expertise.