[TexasFreeper2009]

They certainly are not spectators, if they can't be identified as known law enforcement at the scene I would find them extremely suspicious.

[rockabyebaby]

They certainly are not spectators, if they can't be identified as known law enforcement at the scene I would find them extremely suspicious.

These guys could be undercover cops, if not, you do realize that there are businesses and restaurants right there at the finish line. They may not be cops or spectators but it doesn't mean the are suspects. A lot of people work in the area and yes businesses are open during the marathon so these guys could have been coming from a store.

[Old Teufel Hunden]

"They certainly are not spectators, if they can't be identified as known law enforcement at the scene I would find them extremely suspicious."

Let's assume these guys are "persons of interest". Let's even assume they are the bombers. They have baseball caps and dark sunglasses on. We have really no way of identifying those guys. There's no facial recognition software that could be used. I really believe this is a useless endeavor because I don't see how they are going to be able to track the bombers down through these pictures.