By Jamie Crawford
The U.S. homeland security chief says chaos and instability in Syria remain a top concern for protecting the country from attack.
"I would say that for those of us in national security and homeland security in this government, this particular issue is at the top of the list or near the top of the list for us," Homeland Security Secretary told a congressional hearing on Wednesday.
In his remarks, Johnson said he has been working with his European counterparts to monitor border enforcement and watch for the movement of would-be terrorists traveling to and from Syria.
Johnson was testifying before the House Homeland Security Committee.
"We see more and more jihadists pouring into Syria for the fight in the rebel forces who have been now infiltrated by al Qaeda affiliates," the panel’s chairman, Rep. Michael McCaul, said.
"It's becoming one of the largest training grounds now in the world, in my judgment, surpassing" the tribal areas of Pakistan, he said.
In addition, Johnson heralded constant vigilance toward aspiring terrorists already in the country like the two brothers accused in the Boston Marathon bombing last year.
"I am also concerned about those who self-radicalize," Johnson said. I think that the Boston Marathon bombing may be a sign of the future. And in many respects, those threats are harder to detect,” he said.
“And so working with state and local governments, first-responders, police commissioners, fire departments, funding, training, preparedness," are critical to addressing the threat, he added.
Johnson also called for an increase in information-sharing between the intelligence community and homeland security officials, calling such cooperation "key" in carrying out their missions.