Two gigantic idiots - walking the streets together, around corners carrying heavy backpacks. Can't fathom how they didn't know with todays surveillance and a million people taking photos that they wouldn't get spotted.
Like I said, from what they have shown us Suspect #1 might not have been involved at all.
Source: http://en.wikipedia.org/wiki/Prepaid_mobile_phone
So basically a phone that can't be tracked to you and you can get rid of and replace easily.
