Transcript for How authorities linked Florida man to suspected package bombs case
Federal authorities revealing much more about how they found their suspect, and about the bombs themselves. Investigators say the devices contain materials that give off heat and energy, capable of doing a lot of damages. They were concerned the intent was to maim or kill. Pierre Thomas on what the bombs contained. Reporter: Tonight, inside that critical moment that led authorities to the suspect. 24 hours ago, police delivered a potential bomb to FBI headquarters. They discovered a latent fingerprint on one component. Once I knew we had a print, I was confident we would be able to find a person. Reporter: Authorities found a match, and the suspect was identified, Cesar sayoc, whose fingerprint was in the system from previous arrests. And the evidence kept pouring in. The FBI was using powerful microscopes to look for DNA evidences. And according to the FBI, it was recovered from two devices. Tonight, the FBI director warning the devices were dangerous. They did contain energetic material which, if subjected to the right combination of heat or shock or friction, could be dangerous to the public. Reporter: Inside the packages, clues. Certain of the mailings included photographs of the target. Recipients marked with a red “X.” And prosecutors say on Twitter, sayoc misspelled Hillary Clinton’s name, with just one “L.” To see it up close in reality is something to behold. A remarkable day to watch unfold. Pierre, they’ve made an arrest, but there is still a lot more work to be done. There’s still concern about whether there could be more bombs out there, and where they were made, right? Reporter: The investigation is far from over. There’s still critical questions. Where were the devices made? Was anyone else involved? Are there other devices out there already in the mail? David?
This transcript has been automatically generated and may not be 100% accurate.
