from slate.com: The NSA has a diverse range of surveillance capabilities—from monitoring Google Maps use to sifting
through millions of phone call records and spying on Web searches.
But
it doesn’t end there. The agency can also track down the location of a
cellphone even if the handset is turned off, according to a new report.

On Monday, the Washington Post published a story
focusing on how massively the NSA has grown since the 9/11 attacks.
Buried within it, there was a small but striking detail: By September
2004, the NSA had developed a technique that was dubbed “The Find” by
special operations officers. The technique, the Post reports,
was used in Iraq and “enabled the agency to find cellphones even when
they were turned off.” This helped identify “thousands of new targets,
including members of a burgeoning al-Qaeda-sponsored insurgency in
Iraq,” according to members of the special operations unit interviewed
by the Post.


It is not explained in the report exactly how this technique worked.
But to spy on phones when they are turned off, agencies would usually
have to infect the handset with a Trojan that would force it to continue
emitting a signal if the phone is in standby mode, unless the battery
is removed. In most cases, when you turn your phone off—even if you do
not remove the battery—it will stop communicating with nearby cell
towers and can be traced only to the location it was in when it was
powered down.

In 2006, it was reported
that the FBI had deployed spyware to infect suspects’ mobile phones and
record data even when they were turned off. The NSA may have resorted
to a similar method in Iraq, albeit on a much larger scale by infecting
thousands of users at one time. Though difficult, the mass targeting of
populations with Trojan spyware is possible—and not unheard of. In 2009,
for instance, thousands of BlackBerry users in the United Arab Emirates
were targeted with spyware that was disguised as a legitimate update.
The update drained users’ batteries and was eventually exposed by researchers,
who identified that it had apparently been designed by U.S. firm SS8,
which sells “lawful interception” tools to help governments conduct
surveillance of communications.


In recent weeks, the NSA’s surveillance programs—both domestic and
international—have been the subject of intense scrutiny following a
series of leaked secret documents. The NSA says
that a vast database that it maintains on phone calls made by millions
of Americans does not include location data. But the revelation that the
agency has developed a technique that apparently enables  it to monitor
thousands of cellphones—even when turned off—is likely to only inflame
civil liberties groups’ concerns, prompting further questions about the
full extent of the agency’s spying efforts.