NOEL KING, HOST:
Investigators are still searching for the person or people responsible for sending 10 suspicious packages to political and public figures around the country. We're going to keep updating you this morning with the latest on that investigation. But first, we're going to take a step back and look at how law enforcement has dealt with dangerous mail packages in the past and how that's informing this current probe. Joining us now is NPR's national security correspondent, Greg Myre. Hi, Greg.
GREG MYRE, BYLINE: Hey, Noel.
KING: All right, so the government is putting a lot of resources into this investigation. This is not the first type of investigation or investigation of this sort in the country's recent history. What have investigators learned from those earlier probes?
MYRE: Well, first of all, we know these are relatively rare. Going all the way back to 1970, there have just been 57 package bombs and 23 additional cases of dangerous materials, like anthrax or ricin. These figures come from the START Consortium, which studies terrorism at the University of Maryland - been fewer than 20 deaths.
But one big change, some of the cases in the past were very, very hard to solve. The Unabomb - the Unabomber was on the loose for 17 years. There was the anthrax case that killed five people in 2001. That went on for seven years. And then the suspect - the main suspect was - committed suicide before he could be charged. So technology now has made it much easier to track people, as intrusive as it may be.
KING: What are some of the technologies, and how do law enforcement officials use them?
MYRE: So the deterrence really begins before a package is even mailed. I mean, we just have surveillance cameras everywhere, certainly at a post office or a FedEx facility. You're likely to be on videotape before you send a package. And then a lot of packages are actually photographed and X-rayed. And as you know, they can be tracked throughout the journey. And then, as they get toward the destination, if you're a - if it's a sensitive government facility or an important official, there are these offsite mail facilities.
And that's come into play twice recently. We've seen packages that were headed to the private homes of Hillary Clinton and Barack Obama. Those were picked up at offsite facilities. And a letter to James Mattis just a few weeks ago at the Pentagon that had ricin in it, that also was stopped at the Pentagon's offsite facility.
KING: Back in March, you remember there was this series of package bombs that terrorized Austin, Texas, and that area. Were some of these techniques part of that investigation?
MYRE: Yeah, they were. Now, that was a case where - several bombs, two people were killed. Several were injured. And then a package exploded at a FedEx station.
KING: Yeah.
MYRE: And that was - or a FedEx Office - and that was really the break they needed. They go back. They look at the surveillance tape. They find a suspect. And then they can do all sorts of things. They can check phone records. Who was in that area? Your phone is a GPS tracking device. Who was in there at the time? They can check the street and highway cameras that read license plates. So all sorts of things start to come into play. There's so many ways to be tracked now.
KING: So the technology is getting better. Do you think it's also fair to say that bomb squad teams are getting better?
MYRE: Yes, they are - and for a reason that may surprise you. I spoke with William Braniff, who's the director of that START Consortium at the University of Maryland that I mentioned. And he explained where this new generation of investigators is coming from.
WILLIAM BRANIFF: These are individuals who may have spent lots of time over in places like Afghanistan and Iraq dealing with improvised explosive devices on a daily basis - so massive learning curve in those conflict zones.
MYRE: So that's about the most intensive on-the-job training you can get, in a place like Iraq or Afghanistan. And as these guys come back, they're going to places like the FBI, the ATF and local bomb squads.
KING: Oh, so they're all benefiting from the experience. NPR's national security correspondent Greg Myre. Greg, thanks so much.
MYRE: Thank you. Transcript provided by NPR, Copyright NPR.