The House Homeland Security Committee has called for U.S. officials to explain how two al Qaeda-affiliated operatives were resettled by a refugee program in Kentucky in 2009 and what has been done since to keep other potentially deadly terrorists from slipping into America's heartland.
House Homeland Security Committee Chairman Rep. Michael McCaul, R-Texas, along with three Republican subcommittee chairmen, sent a letter Friday requesting a briefing from Alejandro Mayorkas, Director of U.S. Citizenship and Immigration Services, saying that "despite security enhancements made to the refugee screening process over the last few years, the Committee remains concerned that terrorists seek to exploit the United States' and the United Nations' refugee programs."
The lawmakers crafted the letter two days after an ABC News investigation revealed that potentially "dozens" of terrorists may have been allowed inside America's borders through the refugee programs.
READ Exclusive: US May Have Let 'Dozens' of Terrorists Into Country as Refugees
The ABC News report also revealed new details about the 2009 case of Waad Ramadan Alwan, 32, and Mohanad Shareef Hammadi, 26, who came to the U.S. from Iraq as war refugees and were resettled in Bowling Green, Kentucky. Not only had both men been previously detained in Iraq on suspicion of terrorism -- during which time Alwan allegedly confessed to being an insurgent -- but both were later nabbed in an FBI sting operation attempting to continue their war against the U.S., this time from inside its borders.
The FBI said that before he was caught, Alwan bragged to a confidential informant about killing U.S. soldiers in Iraq. Alwan and Hammadi pleaded guilty to terrorism-related charges in 2011.
Representatives for the U.S. CIS referred an ABC News request for comment on the letter to the Department of Homeland Security (DHS). DHS spokesperson Peter Boogaard said the department "will respond directly to members of Congress, not through the press."
Boogaard previously told ABC News for its original report that the U.S. government "continually improves and expands its procedures for vetting immigrants, refugees and visa applications, and today [the] vetting process considers a far broader range of information than it did in years past."
"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 Boogaard said.
Department of Homeland Security officials have previously appeared before the House Homeland Security Committee to answer questions about the Kentucky case.
Additional checks were added to the vetting system in 2010 and there has been an "appreciable increase in [DHS'] ability to identify derogatory information on Iraq refugee applications," according to December 2012 testimony from Dawn Scalici, then-Deputy Undersecretary of the DHS' Office of Intelligence and Analysis.
Scalici said then that "retroactive" background checks on refugees were still underway.