FBI Director James Comey warned Congress on Tuesday that homegrown terrorist attacks are an increasing threat to the United States, particularly as the Islamic State continues to lose territory in Iraq and Syria.
While the number of Americans traveling to Syria to join ISIS has diminished over the past year, Comey said law enforcement and intelligence agencies remain highly concerned that jihadists from Western nations will pour out of the Middle East and pose new threats as the so-called caliphate is "crushed," the Associated Press reported.
"There will be a terrorist diaspora sometime in the next two to five years like we’ve never seen before," Comey testified before the Senate Homeland Security and Government Affairs Committee.
The hearing came a week after the linked bombings in New York and New Jersey and the ISIS-claimed stabbing spree at a Minnesota mall.
Homeland Security Secretary Jeh Johnson told the panel that terrorist threats have evolved since September 11, 2001, from terrorist-directed attacks "to a world that also includes the threat of terrorist-inspired attacks" where a lone actor living in the U.S. is "self-radicalized" to carry out an assault.
Johnson said intelligence and law enforcement agencies have difficulties detecting terrorist-inspired and terrorist-enabled attacks because they can take place with little planning.
Sen. Ron Johnson (R., Wis.), who chairs the committee, said the latest attacks in the U.S. provide evidence that the threat of "militant Islamic terrorist attacks to the United States remains significant." He said extremist Islamic terrorists have killed 63 people in the U.S. since last year.
Though Republican presidential nominee Donald Trump has suggested a temporary ban against Muslims from traveling to the U.S. to mitigate terrorism concerns, Jeh Johnson said the U.S. needs to instead focus on "building bridges to diverse communities."