Exclusive: Fake cellphone tower likely surveilled protesters at Portland ICE facility

So I traveled to the ICE facility in Portland, Oregon, which has been the site of ongoing

protests since June in response to President Donald Trump's immigration policies. I used an academic research tool called Marlin to scan the cellular signals being sent from

cell towers to cell phones in the vicinity of the ICE facility in order to look for a

device called a cell site simulator. This is also called an MC catcher or a stingray

So cell site simulators basically mimic legitimate cell phone towers. And when they're brought into an area, they broadcast a stronger signal than real towers in the area, which forces your phone to connect to it

And then they use that to obtain your IMSI or your International Mobile Subscriber Identity, which is a unique 15-digit code tied to your SIM card that the network uses to identify you when you're using your cell phone

In multiple 24-hour-long test scans, Marlin's researchers found a median of less than 3% of the messages being sent from a legitimate cell phone tower asked phones for this unique identifier

And in their multiple tests, the researchers found that spikes above 10% were rare and

never exceeded 14%. In contrast, in just 14 hours of scanning, I saw over half a dozen spikes surpassed 10

and recorded three separate 18 spikes in just a one window But when I started to walk away to a nearby hotel about 0 miles away that percentage started to drop back down to what the normal baseline number is

that you'd expect to see from a normal tower behaving normally. So when you see huge spikes

of those type of IMSI exposing messages, that's indicative of a cell site simulator being used

So if one of these devices is running at a federal facility, for example, they can find out

all the phones that were in that area at a certain time. In this instance, it's likely that there was a device attached to a building

that was looking at the people in the area. The reason cell site simulators are so controversial is that even if you're looking for a specific device

you have to force all other devices in the area to connect to you. So even if you have a warrant to find a specific phone

you're essentially siphoning up other people's data in the process. And while warrants are required, cell site simulators can be deployed without warrants

under certain emergency circumstances, such as issues related to national security. So that raises the question of whether that justification is being used to potentially

surveil protesters. And given that there was an apartment building and other businesses directly across the street

from the ICE facility, even people unrelated to the activity on the ground may have had

their information swept up