Via eavesdropping, terror suspects nabbed

R. A. Hettinga rah at shipwright.com
Wed Jun 2 12:14:39 EDT 2004


<http://www.csmonitor.com/2004/0602/p02s01-usmi.htm>

The Christian Science Monitor
from the June 02, 2004 edition -
http://www.csmonitor.com/2004/0602/p02s01-usmi.html

Via eavesdropping, terror suspects nabbed
Intelligence officials use cellphone signals to track Al Qaeda operatives,
as number of mid-level arrests rises.

By Faye Bowers | Staff writer of The Christian Science Monitor

 WASHINGTON - An ordinary-looking grid map of Riyadh adorns one wall of a
command-and-control center deep inside a government building in Saudi
Arabia's capital.


The map is higher-tech than it appears at first glance. Tiny embedded
lights flash red when certain cellphones - those belonging to suspected
terrorists - initiate or receive a call. Teams of officials from Saudi
Arabia, the FBI, the CIA, and the US Treasury Department decide instantly
whether simply to watch and listen to the suspected terrorist - or to send
in screaming police cars to nab him.

So far, officials say, this technology - and others - has enabled them to
interrupt several terror plots and nab dozens of suspected terrorists.
Certainly it hasn't served as a panacea, as the attacks on foreign workers
in Saudi Arabia's oil-worker compounds last weekend show. At least 22
people, including one American, were killed when terrorists stormed a
compound where foreign oil workers lived. One terrorist was captured, while
three others escaped using hostages as shields.

It doesn't take long for terrorists to figure out how authorities are
tracing them and then change methods. Still, the technology has proved
helpful in rolling up cells in Europe, the Middle East, Southeast Asia, and
America. "Today, gumshoe is really a lot more electronics," says Peter
Crooks, a retired FBI agent who specialized in counterterrorism. "They have
some pretty sophisticated equipment."
Recent progress

Cooperating officials in many countries have been quietly chipping away at
terror cells over the past several months. Recent progress includes:

* Japan arrested five foreigners with suspected ties to Al Qaeda on May 26.
Pakistan had detained four others on May 24.

* The Saudi government killed five suspected militants in the Buraida area
on May 21.

* On May 6, the Philippines arrested an alleged cell leader with Jemaah
Islamiyah, a Southeast Asian group tied to Al Qaeda.

* Spanish police arrested a Moroccan April 27, and said it was seeking five
others for roles in the March 11 Madrid train bombings. So far, 19 have
been detained for their roles in those bombings.

* South Africa deported five Al Qaeda members on April 9. Government
officials there claim the moves led to the detentions of several others in
Jordan.

* Jordan foiled what it called the most serious attempt yet to overthrow
its government on April 9. Four terrorists were killed and three detained
after they attempted to use chemical weapons and truck bombs against
several government targets, including the prime minister's office and the
US Embassy there.

Terrorists, of course, catch on to the new tracking procedures and seek
safer ways to communicate. Osama bin Laden, for example, stopped using
satellite phones because he found out - with the delivery of a guided
missile - that the US was tracking his position via the satellite.

But terrorists found a new system that enabled them to use phones that were
difficult, if not impossible, to track.

SIM cards, for Subscriber Identity Model, were developed to create a
universal - and cheaper - cellphone system. Under the old approach, a
resident from, say, Britain would be charged at a local rate when making
cellphone calls in England. But if he were to travel to Germany, he would
be charged long distance rates. Under the new system, he can buy a German
SIM card - which contains a fingernail-sized computer chip - and make the
same calls at local rates.

The information on pricing, minutes, and local telephone numbers is encoded
in the chip. But since there is no need for a local record of the
purchaser's name and credit information, as there is when setting up a land
line or a traditional cellphone account, it makes it easier for people to
use phones undetected.

"What we're seeing is that people who want to remain invisible to law
enforcement are doing things like this in order to evade interceptions,"
says a telecommunications engineer who's helped develop ways to track
cellphone users. Still, he adds, "this doesn't make you immune from
interceptions."

After years of tracking terrorists, investigators have amassed a large
database of land-line and traditional cellphone numbers they are watching
(or listening to). All it takes is a call from one of those numbers to a
phone with a SIM card to discover who's using the undetectable phone.
How one arrest happened

This is what led investigators to Khalid Sheikh Mohammed, the mastermind of
the 9/11 plot, who was arrested in Pakistan in March 2003. A suspected
terrorist whom German authorities were watching placed a call to someone
with a cellphone in Pakistan on April 11, 2002.

No one spoke. But authorities said the call was made to alert Mr. Mohammed
that an attack on German tourists visiting Tunisia was about to take place,
which it did, later that day. Authorities began tracking the SIM card,
which Mohammed supposedly moved from phone to phone, creating problems in
locating his position.

But pinpointing the location of the phone was much easier. Investigators
tracked it by analyzing the signals from different cellphone towers. The
time it takes a signal to "propagate and return back tells how far the
cellphone is from the tower," says an engineer. The reason the red lights
flash so quickly in the Saudi command and control center is that "the
timing is nearly simultaneous," he says.


-- 
-----------------
R. A. Hettinga <mailto: rah at ibuc.com>
The Internet Bearer Underwriting Corporation <http://www.ibuc.com/>
44 Farquhar Street, Boston, MA 02131 USA
"... however it may deserve respect for its usefulness and antiquity,
[predicting the end of the world] has not been found agreeable to
experience." -- Edward Gibbon, 'Decline and Fall of the Roman Empire'

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