— -- ANNOUNCER: ABC's This Week. It's Super Bowl Sunday and the countdown is on. Just hours to go until the biggest game of the year. And we're going behind the scenes. The intense new security measures officials are taking right now.
Measles outbreak: the frightening new cases this weekend. Are thousands now at risk? How can this scare be contained.
2016 shocker: Mitt Romney is not running. What that means for the other GOP contenders. Our exclusive interview with the man some say could now be 2016's biggest surprise.
From ABC News, This Week with George Stephanopoulos begins now.
Right now, final security preparations. Authorities are taking no chances with incredible measures in place throughout the Phoenix area.
ABC's Pierre Thomas has an inside look.
PIERRE THOMAS, ABC NEWS CORRESPONDENT: As more than 65,000 fans head to the Super Bowl today, many will be greeted by specialized teams of bomb sniffing dogs and officers wearing these radiation detectors.
Everything tracked by surveillance cameras feeding into this command center. Undercover officers posing as fans among the crowds, SWAT teams nearby.
No specific credible threat has been identified, but there's growing concern about so-called lone wolves radicalized on the internet.
UNIDENTIFIED MALE: We have more concerns about domestic-based acts of violence inspired by things people may see or read on the internet.
THOMAS: So nothing left to chance.
Every item delivered to Super Bowl stadium, more than 14,000 trucks worth, has been screened. These massive homeland security x-ray trucks allow this officer to see everything inside.
Everything gets checked out.
UNIDENTIFIED MALE: We've got the porta potties. We've got everything: food, hotdogs, hamburgers, the NFL paraphernalia.
THOMAS: So bottom line, what are you looking for?
UNIDENTIFIED MALE: We're looking for any weapons. Any bombs, any weapons of mass destruction.
Today above the stadium, a squadron of air power to enforce a 30 mile ring of restricted air space.
As I got on board this U.S. Customs Blackhawk helicopter it was clear authorities are deadly series.
To the people that would say, oh, this is all overkill. You don't need all these assets to protect the game, what's your response?
UNIDENTIFIED FEMALE: You never know. You've got to be prepared.
THOMAS: Any rogue aircraft that fails to respond, could be shot down by fighter jets like the one I flew in before last year's Super Bowl.
We caught up with the homeland security secretary exclusively as he came to personally inspect the protection plan.
Mr. Secretary, I see that pretty big sign. Is that how you're trying to frame security here?
JEH JOHNSON, HOMELAND SECURITY SECRETARY: We want the public engaged in our efforts. We want public participation, public vigilance.
THOMAS: As for that other huge security story Deflategate?
Have you been asked to do any security on the footballs?
JOHNSON: No. Nor do I have a team I'm rooting for. I'm rooting for a safe and successful event.
THOMAS: For This Week, Pierre Thomas, ABC News, Glendale, Arizona.
RADDATZ: All right, thanks to Pierre.
Now let's bring in Arizona Governor Doug Ducey. Good morning, governor. A great day for the state of Arizona.