Transcript for Terror Suspect Shot and Killed in Boston
He turned they are so vast. The game gave several commands. For him to drop the weapon. And unfortunately became happy offices and you know they do what they were trained to do it. From FTSE. They had to take a life and that's never easy decision for any opted to give. A nine wielding man shot and killed earlier today in Boston. But the suspect using what officers called in military style knife had been under surveillance by the joint terrorism task force. I'm Caroline Costello in New York joining me now with the latest ABC's Aaron could her ski. Harrington at this hour what do we know about how this all came to be about. This all started at about 7 o'clock in the morning when an officer from the Boston Police Department and an FBI agent from the that the Boston office of the FBI approached a man who had been under surveillance we don't know the man's name yet. Or why he had been under surveillance by the joint terrorism task force but they approached in a in a CVS parking lot of pharmacy parking lot. In the Roslindale section of Boston. And when they did apparently according to the Boston Police the man came at them with some kind of military style knife is how the weapon was described. There were as you heard from Boston Police Commissioner Bill Evans there repeated commands to drop the weapon when the suspect refused and kept coming at. The two law enforcement officers that's when they opened fire the man was wounded at the time taken to Brigham and Women's Hospital in Boston. And that's where he died. Aaron is that at this point we don't know how why or when this person came to be surveying by the joint terrorism task force. Do we know just how individuals in general. Catch the attention of the FBI and and the FBI starts to watch them. Well there are so many different ways it could have been a tip it could have been something that somebody caught on line it is could have been a number of things. But the idea that he was under active surveillance and we're told he was under active surveillance for several weeks. Is is an indication. That authorities were taking him quite seriously we've heard for so long over the last several months how taxed the resources of the FBI are. And trying to catch these so called. Homegrown radicals that dogs are just being inspired whether by crisis or al-Qaeda or some other kind of terror propaganda their reading online. And how difficult it is for the FBI to actually try to catch these people until they either try to travel overseas or carry out something here in the United States. In this particular case with this particular individual law enforcement seems to have had enough to go on. That the man warranted active surveillance. And now and that's part of the reason why he was approach today. And and when he was we know he was armed but that military style night. You mention the system being taxed. This deadly incidents where the suspect known to have terror connections comes right after I keep Patriot Act provisions just expired how big of a deal is this is this going to be come part. Of the national and political conversation. Well it certainly could they added there's enough room for politicians to the case here in any time that the the authorities lose an ability. That they has deemed important in the counterterrorism effort. They're going attempted to to raise hell about it and we've heard from the FBI director the attorney general talking about phys. And and the importance of the they'd be viewed the phone data gathering in retention program that that had just expired the senate is now working on reauthorization. Any time. The authorities lose. Some ability that they like. They get upset about it I think they've also gone around the country and talked about these encryption techniques that phone companies are now using on mobile devices so that. The authorities cannot get access to 22 someone's. IPhone or or or Blackberry or whatever device. And that's also something that the FBI's lamented and they think these tools are critical to catching just this type of person. The authorities right now Carolyn are working to determine whether he was inspired by crisis. And if he was. One of the key ways we know that that happens is is through what happens on line and social media and propaganda. And if authorities can't tap into those kinds of accounts of those kinds of resources. That that that may put them. At a disadvantage of course the other side of the coin is it's not the phone company's job to be counterterrorism investigators on the FBI's going to have to find another way. Okay ABC's Aaron could care ski thanks so much we appreciate it. And you can keep up with this story in real time my gallon in the ABC news app and storing the story for exclusive updates. On the go I'm Caroline Costello in New York.
This transcript has been automatically generated and may not be 100% accurate.