The chairman of the House Homeland Security Committee said Friday the shooting at two military facilities in Tennessee a day earlier -- appears to have a link to the terror organization ISIS.
Congressman Michael McCaul, speaking from MacDill Air Force Base, said the FBI is trying to officially determine whether Muhammad Youssef Abdulazeez had been radicalized by ISIS terrorists through internet communication.
But McCaul had no hesitation making the connection.
"My judgment in my experience is that this was an ISIS-inspired attack," he said. "This is a new generation of terrorists. This is not [Osama] bin Laden in caves and couriers anymore. This is what the new threat of terrorism looks like."
Investigators have said Abdulazeez first fired up to 30-rounds at the Armed Forces Career Center in Chattanooga.
He then drove six miles away to the Navy Operational Support Center, where he killed four Marines.
McCaul, a Republican representative from Texas, was on his way to a pre-planned visit at the base in Tampa when he heard the news.
"Little did I know on the flight down here that terror would strike America," he told reporters. "This is the one that we worried about. This is the one that unfortunately happened yesterday."
McCaul said the U.S. is fighting a seemingly endless battle against the terrorist organization and has had some success thwarting more than 50 plots and making at least 60 arrests on U.S. soil.
But the congressman said the attack in Tennessee is hardest to predict -- carried out by a so-called 'lone wolf'. Inspired by ISIS propaganda and communicating in secret on the internet -- attacking without warning.
McCaul worries the threat is spreading; the government is now conducting ISIS-related investigations in every state, including Florida.
"The threat to the homeland is one of the greatest I've seen in quite some time," he explained, adding ISIS continues to urge supporters to target military personnel and law enforcement.
McCaul believes MacDill Air Force Base is safe but he wants smaller recruitment and training centers to be more secure.
For starters, the congressman suggests ending gun-free zones that ban service members from being armed at U.S. military sites -- a regulation in place since the early 1990's.
Each victim in Tennessee was unarmed.
"If our military fights overseas to defend America, I don't want to put them in a position where they're defenseless here in the United States," he said.
McCaul also issued a warning to terrorists.
"This will no doubt be proclaimed as a victory by them. But we will have the final word."