MELISSA BLOCK, HOST:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block.
ROBERT SIEGEL, HOST:
And I'm Robert Siegel.
The bombings in Boston may raise questions about what might have been prevented and how people responded to the crime, but the biggest question they posed today is: Who did it? A virtual army of state, local, and federal law enforcement agencies are working to answer that question. And understandably, they're not disclosing much. We wondered how you would organize what are literally bits of evidence; either shrapnel, or hundreds of digital stills and videos that onlookers took at the marathon finish line.
And we're going to ask Mitchell Silber of K2 Intelligence - that's a private investigative and consulting firm. Mr. Silber used to be director of the analytic and cyber units in the New York Police Department's Intelligence Division, where he supervised the NYPD's terrorism-related investigations.
Welcome to the program.
MITCHELL SILBER: Thank you.
SIEGEL: Posed with this case, where do you start? What does this big task force do first?
SILBER: Well, the task force is going to have to have a division of labor. Number one: cameras. There are a number of different cameras in that area. They were all recording and some group has to go through that film and manually watch to see if they can see the conspirators placing the devices in the area. Now, in the task force you may have the FBI, the Boston Police Department, the Massachusetts State Police, the Central Intelligence Agency. So...
SIEGEL: Well, let's take that task alone first. You would want to have all the different agencies represented? Do you get some kind of a synergy from that effect or would you rather have one agency handle all of the imagery, say?
SILBER: Well, you might hand that job to one particular agency. It might be the Boston police who are charged with looking at the footage from those cameras. As you analyze the explosive devices, that might be something that the Boston Police Bomb Squad, or potentially the FBI, might handle because of their expertise in analyzing different types of explosive devices worldwide.
SIEGEL: We learned today that the investigators have concluded that pressure cookers, ball bearings and, I believe, nails were used in these explosives. How far down the road to a suspect does information like that take you, if your explosives team has gotten that far?
SILBER: Well, I think it speaks to, to some degree, the sophistication of the conspirators. They're not using some of the devices we've seen in some of the more spectacular attacks, like hydrogen peroxide bombs in the London 7/7 bombings. We're not seeing ammonium nitrate like we saw in Oklahoma City.
Now, in New York, when we had the Times Square bombing in May of 2010 and there was a vehicle-borne explosive in Times Square, one of the things that we were looking for was some of the elements of the explosive device, like a particular alarm clock. There was this very, almost cartoonish-type alarm clock that was supposed to work as the timer. And one of the agencies' responsibilities was to survey local stores in New York City that might have carried that particular alarm clock.
SIEGEL: Did you actually find a store that carried that alarm clock?
SILBER: In fact, we found multiple stores that carried the alarm clock. And that is one of the other challenges. If we're talking about pressure cookers, that might be another direction that the investigators go. Once they've identified what the make and model is of that pressure cooker, if that's possible, is to go back and start to survey stores in increasingly large circles around the bomb blast area, to see what stores might have sold that.
SIEGEL: That sounds like a lot of shoe leather; that somebody is going to lots and lots of stores and talking to lots of houseware departments, if not lots of people who've had garage sales over the past several years.
SILBER: Yes, you're right. And this is why the idea of having a joint task force with different agencies there really provides that synergy. Those are the types of jobs that are going to go to a large degree to the locals, who've got the manpower, who know the geography, know the stores, and are best suited to go do that job.
SIEGEL: Well, Mitchell Silber of K-2 Intelligence, formerly of the New York Police Department, thanks for talking with us.
SILBER: Thank you. Transcript provided by NPR, Copyright NPR.