[CedarDave]

Located him through "cell phone triangulation" ...

How can you locate a suspect that way if you don't have a name or phone number? F&F suggesting they picked up the trace from just his presence at the FedEx office. If he didn't use his phone there how can they trace him? Do cell phones leave a digital trace everywhere you go? If I go to McDonalds at 4 pm for a burger, can the Feds hours later get all cell phone data from everyone who was there at that time even if they didn't use their phone?? Scary!!

[ifinnegan]

“Do cell phones leave a digital trace everywhere you go?”

They constantly ping the nearest cels towers.

So, yes.

[bray]

Once they get the cell phone number they can track your movements since you owned it. He would have been to all the bombing locations and then track where he would be now.

[Mom MD]

digital phones ping the cell towers even if not in use.

[RitchieAprile]

https://en.wikipedia.org/wiki/Mobile_phone_tracking

Probably got his phone’s unique IMEI at the FedEx office from a roaming signal and were then able to track based on subsequent roaming signals. Since they had the suspect, his phone, and video confirmation in one place, they could then look for where that IMEI showed up (cell tower roam logs).

[Oldeconomybuyer]

As detailed by Business Insider, the feature is quite easy to access if you know where to look – furthermore, it’s equally easy to turn this particular kind of location tracking off if you’re not comfortable with it.

What you have to do is go to Settings, then Privacy, then Location Services. Once there, tap the System Services menu and look for the Frequent Locations menu at the end.

If you then tap on that option, you’ll get a list of the recent places you have been, as tracked by the iPhone. Pressing on any of the listed cities will get you access to a map that will show you exactly where you have been tracked by your smartphone in that city.

From the same Settings page, you can choose to erase your location history and even turn the feature off so that your phone no longer saves your location data.

A step-by-step guide for accessing this hidden iPhone menu is available at the source link, complete with relevant screenshots.

https://bgr.com/2015/04/01/iphone-location-tracking-map/

[CodeToad]

“How can you locate a suspect that way if you don’t have a name or phone number?”

Simple: Gather all the pings for each bombing location. Is there a single number that was at each one? Yes? Then there is your suspect.

[TheBigJ]

They check the cell towers in the area and associated numbers pinging. CIA developed a unit called Stingray many law enforcement uses, it's very expensive and simulates a cell tower, however it can also track a certain number to a certain room with that cell in a big apartment bldg for example, it is also believed it captures sms messages. However stingrays similar devices have been struck down by court for violating privacy, not sure where it stands now. One can go untracked by using a faraday bag-- an electronic black hole, or using burner phones, though if you had a crack team after you the counter measures have to be more careful. For example pay as you go phones can be traced by their registration at the register to the store, which means cash and disguise, or simply shutting down the surveillance system but I'll go ahead and stop here😉

[21twelve]

“Do cell phones leave a digital trace everywhere you go? If I go to McDonalds at 4 pm for a burger, can the Feds hours later get all cell phone data from everyone who was there at that time even if they didn't use their phone?? Scary!!”

I believe that even if your phone is “off” - it is still sending out a signal. Unless you remove the battery and/or simm card. But definitely if it is still on.

It would take some computer time - but probably not a huge amount to look at an X hour window prior to each blast and see if any of the same phones were in proximity to the various sites.