I have to assume the local police and any other organization involved in the investigation are constantly being contacted by folks who believe they have information that will help them with the case. I would be willing to put some money on the idea that someone provided some kind of information worth looking into. Neighbors are starting to talk a little bit now. I believe some co-workers and other acquaintances are being more vocal. I would imagine these are the kinds of people that can provide information about stuff they don't even realize helps the investigation. And, it does not surprise me that they are 5 or 6 deep when they rolled up on PF.
Crazy story real quick, I went attended the State University of New Jersey. I was a junior there when 9/11 happened. A few months after those events I stopped at a small store to grab something to eat. Similar to one of those bodegas in NYC. There were two middle eastern gentlemen behind the register. One rang me and the other guy was sitting on a stool just behind the guy ringing me out. He was reading a book. It was a book that used to be one of the required readings for anyone working towards their private pilots license. How I know the book is a completely different story that I am not going go through right now. Anyways, given recent events close by I couldn't help but get suspicious. I called my grandfather when I got home. My grandfather was a retired Air Force 4 Star General. Almost the highest rank one can be in that branch. He had a ridiculous amount of flying hours and he ran the Pentagon for a period of time. I told him about what happened. 3 or 4 days later, as I was walking out of one of my classes I was approached by 3 men in suits who told me they needed to speak with me. We walked to their SUV that was parked in a fire lane, got in, drove away to another building on campus and we had a discussion about the guy I saw reading the manual in that store. There were two other SUVs following the guys I was with that day. Whoever was in them never got out. I never saw any of them. Come to find out my grandfather made some calls after our talk. The FBI got involved and that was who questioned me that day. For whatever reason, they travel in numbers.
My point here, I figured out very quickly that the FBI can find anyone, anywhere at any point in time. If they need to get something done and they have the right information, I believe they are able to figure out just about anything. I have no idea what steps they took to find out which class I was in, which campus it was on and what time I would be getting out of it. They knew my girlfriend's name. They knew what street I grew up on. It was fascinating. It was the scariest thing I have ever been through but, still fascinating. If someone is guilty of a crime and those people are questioning that person, the individual would have to be some kind of sociopath to be able to maintain composure while being questioned. I have to believe that if the FBI had any real evidence, on anyone involved with this, it would have been wrapped up well before now.