Authorities are on high alert, setting up an underground command center, and we got an exclusive inside look. ABC's chief investigative correspondent Brian Ross is in Boston. Brian? Reporter: Good... See More
Authorities are on high alert, setting up an underground command center, and we got an exclusive inside look. ABC's chief investigative correspondent Brian Ross is in Boston. Brian? Reporter: Good morning, Martha. The Boston police commissioner told me that his only real fear tomorrow is a copycat attack. He's spending millions of dollars to make sure that does not happen. The city seems in a festive mood, with a record number of runners, some 36,000 signed up to run this year's marathon, but it's all deadly serious, inside what's known the bunker, the underground high-tech control room, where he showed us around. More than 100 newly-installed cameras along the 26.2 route will be monitored, twice as many as last year. We have expanded across the board. Reporter: Last year's surveillance cameras helped to pinpoint the alleged bombers, but only days after the attack. This year, the goal is to stop an attack before it happens. Any person is presenting a concern to us, may be monitored very quickly. Reporter: In addition to the cameras, some 4,000 police officers will be on patrol along the route, 500 of them will be undercover in order to keep the festive spirit from being overwhelmed by the police. I don't want it to be an event where people feel intimidated by the police presence. Reporter: Boston's new police commissioner, bill Evans will be on duty all day this year. What will you be looking for? Someone who doesn't feel right. Characteristics. Lot of our officers underwent training for characteristics of someone who might be carrying explosives. Reporter: Evans' officers have already put their training to the test, during a memorial tribute this week, a backpack turned out to have a rice cooker with confetti in it, it was a hoax but the bomb squad was taking no chances. It was a nice drill. We did what we were trained to do. Reporter: The winners of last year's marathon, were all but forgotten because of the bomb attack, but they're back this year. I came here to support, yeah. Reporter: You're not scared about running? Not, I'm not. Okay, I'm not scared because I know there's security. Reporter: There's no intelligence whatsoever that there is a possible attack that this is target of any terrorists. Of course, that was the case last year, too. Martha? Thanks, Brian. Chairman Mccaul is back with us, along with former NYPD commissioner ray Kelly, now an ABC news contributor. Welcome again to you chairman Mccaul. And commission er Kelly. I want to start with you, Mccaul, Boston is now the safest place on the planet, do you agree? Are you that confident? I talked to the Boston police commissioner, and our homeland security operations on the ground, I believe it's very ramped up securitywise. Cameras. All sort of bomb-detecting equipment. I think it's very well-fortified. I'm concerned, as was noted, a copycat demonstration or someone who's inspired by the tsarnaev brothers to person Tate another act. That's real scenario. We don't have any real evidence. We didn't have that last time. The good news is, since the last time, after we have done our reports and investigations on what happened last time, now we're having full cooperation with the FBI, in terms of on the ground security, so, I feel confident we're going to have a safe and successful marathon tomorrow. I know the entire nation is cheering for Boston. They certainly are, commissioner Kelly, nobody knows how to keep masses of people safe like you do, but what do you look for specifically? We're talking about 26.2 miles here. No question about it. It's a long distance to secure, I think what you look for are abnormalities. What we used to say, you look at your world through the prism of 9/11. Now, the officers, the spectators have to look at their world from what happened on April 14th, 2013. From my perspective, I think the Boston authorities have done everything they reasonably can do to make this a safe and secure event. You can reduce the risk. But you can't totally eliminate it. It's important to note that this race goes through eight towns, including Boston, so that means you need a lot of coordination and a lot of communication, and that's what the authorities have been focusing on for a better part of the last year. I think last week, governor Patrick said they had a tabletop exercise involves 450 people, to me, that shows they're looking at the right things, because if something happens outside of Boston you have to respond. Commissioner, tell me then what worries you most about tomorrow. Obviously, some sort of copycat event. Something that looks similar to what we saw last year, and again, you cannot totally rule out an event happening away from the marathon. And I believe that the Massachusetts authorities and the Boston police have put that into the equation, you need resources to respond to locations away from the marathon if something untoward happens. And chairman Mccaul, the report from your committee, said the FBI failed to fully act on the intelligence it received last year about tamerlan tsarnaev. Quickly, if you will, could we have stopped this last year? Well, you know, my report, also the inspector general came out with a report, saying investigative steps weren't taken when the FBI were investigating tamerlan tsarnaev. Interviews were not taken, leads were not followed up. Warning signs were sort of missed. So, could it have been stopped? Well, I think the overseas travel was the key here. We missed that completely. Even the FBI supervisor said that was a significant event that, quite frankly, would have changed everything had the case agent on the ground reported that to his supervisor. Thank you, chairman. Up next on this Easter Sunday -- our closer look at the
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