8 pre-attack indicators of terrorist activity

As we approach the 10-year anniversary of the 9/11 terrorist attacks, it is a very useful exercise to remind ourselves about some of the most basic — and most visible — signs which can help police officers thwart a plot


There are observable behaviors and activities prior to a terrorist attack which generally represent the best opportunity to detect and disrupt the terrorists’ plans. What follows is a synthesis of similar resources that can be found online as well as information gleaned from a variety of books I’ve read on the subject. This not intended to be a complete or comprehensive list. It’s a starting point for a much larger discussion, so add your own thoughts on this in the comments area.

1.) Financing Activities — Watch out for evidence of transactions involving large cash payments, deposits, or withdrawals. These are not just signs of criminal enterprise, but also may indicate terrorist funding efforts. Collection/solicitation of financial donations and “white-collar” criminal activities are potential warning signs.

2.) Surveillance — Not just glassing a target with a pair of binoculars, a long camera lens, or a laser range finder, this can include timing the movement of vehicles and persons within an area, as well as simply transiting the area at various times of day and recording the activity levels at the target. Evidence of surveillance operations can also be found at totally different locations — if there are hand-drawn diagrams or building plans in the house you just did a warrant entry on, ask yourself “Why is this here? What could this be used for?”

3.) Active Elicitation — A tactic often ignored is sending spoof “surveys” via fax and email to target locations with questions about security, numbers of employees, and whatnot. Activities in this area can also include in-person or phone inquiries. A parent interested in enrolling their child in a school and asking, “Do you have police officers guarding kids here?” may really be someone looking to commit a Beslan-style attack here in the United States.

4.) Probing Security — This may include abandoning suspicious packages in a target area, breaking and entering a target building, or simple trespass on the target’s property. It’s entirely possible that the person doing this activity has no idea that they’re testing security response — a terror cell with decent operational security will send a low-level person on this task who knows nothing of the attack plan itself. Obviously, this can also include phoning in false alarms to a location and watching the tactics of the arriving first responders (as well as timing their response times).

5.) Acquiring Supplies — In addition to the acquisition of conventional weapons like guns, ammunition, and knives, terrorist cells and individual lone wolves are still seeking to obtain explosives or precursor ingredients. Legally-obtainable but equally-hazardous materials include pool chemicals, fuel, and fertilizer. Further, what are the security considerations at your local hospital regarding the radiological material — including waste products — stored there. With a set of scrubs, a stolen key, a forged ID, and a confident stride, an interloper can gain access to even highly-secured areas of a medical facility.

6.) Suspicious Persons — Perhaps the best possible application of the word “hinky,” all officers are already on the lookout for people who just seem to be out of place. While a lone adult at a playground screams for attention, a middle-aged student enrolled in a chemical engineering class with a bunch of 19-year-old college kids seems to slip a bit beneath the radar. Trust your gut, and ask the question, “What is this person really doing here?”

7.) Conducting Dry Runs — It has long been my personal belief that Richard Reid was unwittingly conducting a dry run when he attempted to light his shoe ablaze on American Airlines Flight 63 in December 2001. Ever since then, travelers have been striding sock-footed through the airport scanners. It’s well known that the 9/11 hijackers racked up frequent-flier miles as they conducted dry runs to count numbers of passengers and time out the best stage of the flight to mount their attack. Dry runs can also be as simple as mapping routes and timing the sequence of traffic lights.

8.) Deploying Assets —  By the time the personnel and materiel are put into motion for a terrorist attack, stopping it becomes considerably more difficult. Once a suicide bomber starts rolling toward target, they’re about 95 percent successful in carrying out their mission. However, there are still viable opportunities to intervene during the final moments before a terrorist act occurs. Never give up!

Many Hands Make Light Work
I’ve been studying terrorism now for more than two decades. My first “desk job” was as a low-level analyst with the U.S. Department of State in the immediate aftermath of Saddam’s August 1990 invasion of Kuwait — my primary area of focus was Middle East terrorism and military history. Despite dedicating a significant portion of my life to studying this stuff, I still work hard to educate myself further about the changing landscape of terrorism.

I know there are thousands of like-minded law enforcers and law-abiding citizens who are doing the same thing. I’d bet a waist-high stack of green money that if you’re reading this final paragraph, you’re one of those great, modern-day American Patriot warriors. With hard work, and a measure of luck, we’ll keep winning this battle against those who want to destroy us.

About the author

Doug Wyllie is Editor in Chief of PoliceOne, responsible for setting the editorial direction of the website and managing the planned editorial features by our roster of expert writers. An award-winning columnist — he is the 2014 Western Publishing Association "Maggie Award" winner in the category of Best Regularly Featured Digital Edition Column — Doug has authored more than 800 feature articles and tactical tips on a wide range of topics and trends that affect the law enforcement community. Doug is a member of International Law Enforcement Educators and Trainers Association (ILEETA), an Associate Member of the California Peace Officers' Association (CPOA), and a member of the Public Safety Writers Association (PSWA). Even in his "spare" time, he is active in his support for the law enforcement community, contributing his time and talents toward police-related charitable events as well as participating in force-on-force training, search-and-rescue training, and other scenario-based training designed to prepare cops for the fight they face every day on the street.

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