In the first year or so after 9/11, just about every major American law enforcement agency started conducting weapons of mass destruction training for its patrol officers. The fear was that al-Qaida might have chemical, biological, and even nuclear weapons and use them to follow up on the stunning attacks on Manhattan and Washington, D.C.

Now, six years later, we still don't know if al-Qaida or other jihadist groups have such weapons.

But there is one weapon of mass destruction that we are certain the terrorists possess and have the know-how to use. They use it every day in Iraq. They've used it frequently in Afghanistan. They've used it for many years in Israel. And this summer, they tried to use it in London and Glasgow.

This weapon is the vehicle-borne improvised explosive device (VBIED), commonly known as the "car bomb." And there's a good chance that the next Islamic terrorist attack on Mainstreet U.S.A. will involve one.

That means that as law enforcement officers sworn to protect the people of your community it is your duty to learn how to counter this threat.

Bad guys have transformed all types of wheeled conveyances, from pushcarts and bicycles to cement trucks and tractor-trailers, into bombs. Terrorists have on occasion even transformed unfortunate four-legged beasts-of-burden into bombs.

This article is intended to give you, the American law enforcement officer, an overview of what you face, how to identify a threat, and what to do when you think you have identified a vehicle bomb.

Note: This article is about the stationary vehicle bomb. Vehicle bombs being driven by homicide/suicide bombers are simply martyr-guided missiles. Only properly setback physical barriers can protect against such attacks. It is unreasonable and unrealistic to expect a lone patrol officer to be able to do anything other than report and stay a safe distance away from a moving VBIED.

Threat Assessment

In 2004, the U.S. Government's Interagency Technical Support Working Group (TSWG) completed a study of trends in the use of VBIEDs worldwide. Although the analysis primarily focused on incidents that occurred between 2001 and 2003, most of the trends identified in the TSWG report have remained consistent. Of special importance for Law Enforcement, TSWG found that:

1) The average number of casualties per VBIED incident is increasing. Some of this statistical increase is attributed to the use of VBIEDs in Iraq starting in 2003. Another factor is the increased use of VBIEDs by Islamist terrorist groups seeking to create mass casualties. This means that local responders must prepare for VBIED attacks as mass casualty events.

2) Attacks against police and military targets account for nearly a third of all vehicle bomb attacks worldwide. Sixty-one percent of these attacks are against static installations. This means that you are a primary target.

3) There has been a distinct increase in the use of creative and sophisticated attack methods, such as multiple VBIEDs, combined attacks (assault teams used in conjunction with VBIEDs), secondary devices, and deceptive delivery tactics. Many of these novel or enhanced tactics are designed to defeat traditional security measures or increase the number of potential casualties. Your preparations must effectively account for multiple crime scenes, follow-on attacks, and the possibility of dismounted terrorists in the incident zone armed with small arms and body-worn IEDs.

Awareness and Detection

According to the TSWG study, 77 percent of vehicle bombs encountered worldwide are concealed inside automobiles; 10 percent inside trucks; and four percent inside vans.

Packed with explosives of various kinds and often also packed with material intended to be shrapnel, these bombs are driven to their target and parked where the terrorists know an explosion will wreak the most death, destruction, and devastation. Detonation is usually accomplished by use of a time-delay mechanism or a cellular telephone trigger.

In automobiles, the most common concealment location for the bulk explosive charge is the trunk. For trucks, it is the cargo-bearing area. Do not think solely in terms of commercial, military, or homemade explosives. The terrorists don't. They know that often it is easier and more effective to hijack an 18-wheeler tanker truck full of gasoline or other nasty chemicals and use it as a ready-made vehicle bomb. As we've seen in Iraq, the resulting damage can be catastrophic.

Bomb Detection

"Go with your gut…that feeling in the pit of your stomach that something just isn't right. Better to be cautious and wrong than dead."

That advice—actually it was more of a recitation of standard operating procedure—was shared with one of the authors during several days of riding along with the Jerusalem Bomb Squad. A significant portion of the Squad's work involves checking out suspicious vehicles.

The advice of the Jerusalem Bomb Squad is advice that you should live by. After all, they know an awful lot about how to locate and neutralize car bombs.

Every patrol officer in your agency should be aware of reports of vehicles stolen under suspicious circumstances such as trucks stolen while empty of cargo, trucks containing hazardous chemicals, or vehicles with distinctive corporate or government markings, license plates, etc. Police should BOLO any vehicles that fit these descriptions.

VBIEDs can easily be made to look like official vehicles, emergency vehicles, and vehicles with handicapped identification. Be alert for such counterfeits. Recently a vehicle being restored as a "patrol car" for use in a movie went unnoticed, parked for days in an official police parking lot. Remember, anyone can make a pretty good facsimile of an emergency vehicle if they have a good painter and the right make and model of vehicle.

Also, look for something that's "out of place." Be aware and use your eyes. Notice if a vehicle is parked illegally, haphazardly, diagonal instead of parallel to the curb, or opposite to the flow of traffic. And ask yourself, does it look like someone hurriedly ditched rather than parked the vehicle? If it does, then you need to consider it suspicious.

In addition, take note of where exactly the vehicle is parked. Is it positioned where an explosion at a certain time would cause mass casualties? Is it placed where an explosion would wreak maximum damage to a nearby structure?

If the vehicle that has caught your attention is a commercial vehicle such as a delivery truck, ask yourself if that type of vehicle even belongs in the area. For that matter, where is the driver? If it does belong, does it belong "here and now?" You know your patrol area, its routines, habits, and deliverymen. Use that information to identify suspicious vehicles.

Sometimes the VBIED from an aborted mission will be ditched or abandoned where its terrorist driver believes an explosion will at least do some damage. We have seen this many a time in Israel.

In one case, a terrorist was frustrated by being unable to get to his intended target because of purposely created, all-morning-long traffic gridlock, so he drove his VBIED into a ground-floor parking area under an apartment building near where one of the authors of this article lives. He had no intention of returning for it later. It detonated at 11:30. Sitting in an apartment two miles away, you could feel the ground shake.

Confirming Your Suspicion

Of course, you can't call the bomb squad to check out every poorly parked car in your patrol area. You are going to have to check it out and see if your suspicions are warranted.

Try to see inside the vehicle. Are its windows tinted, dirty, or covered? If the vehicle's interior is visible, are there propane or other tanks or cylinders of combustible/explosive gas inside? Do you see containers holding liquids? Also check for boxes of nails or any kind of shrapnel inside. Are there wires or fuses in sight? Can you see an unusual box or electronic device near the front seat area (possible arming unit, timer, or triggering device)? Can you see a cellular telephone? Do you see any unusual rust spots around the base of a truck or van (a possible indicator of an ammonium-nitrate-based explosive)?

If you do not see any of the above, are boxes visible inside the vehicle, boxes in which explosives and shrapnel might be concealed? An IED could be hidden behind or among the boxes. If you cannot see inside at all, sniff around for an odor of fertilizer or chemicals or fuel emanating from the vehicle. Another tell-tale sign of a potential bomb is a vehicle that is really "weighted down."

Information Is Critical

You need to determine who owns the vehicle. Use your on-board computer to run the vehicle's registration or, if your patrol car is not so equipped, call dispatch to check out the vehicle.

Make sure that both of its license plates check out. If it is a private individual's vehicle, find out if that individual lives in the area. If the vehicle does not belong to a local resident, get the owner's telephone and cellular phone numbers and call or have dispatch call the person.

Ask the owner where he and his vehicle are presently located. If the suspicious vehicle is a rental, try to make contact with the renter and make the same inquiry. Follow the same procedure for commercial vehicles.

If you cannot reach the delivery person via cellular telephone, consider checking with local residents and merchants in the immediate area. Walk three to four storefronts up and down and across the street from where the vehicle is parked. Is the deliveryman or workman with one of them? Has anyone nearby seen the deliveryman or the vehicle's driver? Accomplish this task quickly.

What if it is a VBIED?

Let's say your gut tells you that you may have a vehicle bomb on your hands. Now, what do you do?

Hopefully your department or agency has a protocol and you have been trained in how to handle the situation you now face.

Here's what that protocol should include. Step one is notification. But be careful. Do not use your patrol vehicle's radio or your personal patrol radio within 100 yards of a suspect vehicle. RF transmissions have been used to detonate terrorist bombs.

So back off and make the call. Provide dispatch with a quick, yet detailed assessment of the situation and scene.

Your next step is to evacuate the area. If you are investigating a suspicious vehicle and you believe it could be a VBIED, initiate evacuation of the area immediately.

According to the TSWG study, the delay time in VBIED incidents is usually under 60 minutes, most often between 30 and 45 minutes. In some cases the delay time can be very short.

In the two most significant VBIED incidents inside the United States, the 1993 World Trade Center bombing and 1995 Oklahoma City bombing, detonation occurred within less than five minutes from the time that the bombs were delivered. Also, if the bomb is designed to be command detonated, the terrorist overwatching the device will most likely detonate the bomb as soon as he or she realizes that the device has been discovered.

If the suspicious vehicle is an automobile, all civilians in the outdoors should be evacuated at least 1,500 feet away (approximately four city blocks). People located indoors within 320 feet (approximately one city block) of the vehicle should also be evacuated. People located indoors beyond 320 feet should take refuge toward the interior of their building and away from windows or weak structural elements.

Guard Against Secondary Attacks

Many terrorist groups target evacuees and emergency responders by concealing secondary devices in the areas where the civilians and rescuers will gather.

Carefully search the areas set up for marshalling of first responders and for evacuation of civilian and non-essential personnel for possible IEDs and additional suspicious vehicles.

In the 1998 bombing in Omagh, Northern Ireland, 31 people were killed when a VBIED parked outside a cordon detonated near a crowd of evacuees. No one searched the evacuation area. Had the evacuation area outside the cordon been searched, police might have spotted the bomb, a stolen car with stolen license plates, parked by itself in a no-parking zone.

You can prevent car bombings. But you have to know what to look for and how to respond when you think a vehicle bomb is in your patrol area.

Car Bombs Are Not New: A Historical Perspective

Vehicles bearing bombs are neither a recent invention nor foreign to American shores.

Many historians trace the use of vehicle-borne improvised explosive devices (VBIED) back to the beginning of the 19th century. In 1800, Napoleon Bonaparte was the target of such an attack while arriving at the Paris Opera. A large charge of gunpowder in the back of a wagon was detonated as his carriage passed. Several decades later Napoleon's nephew, Charles Louis, was the target of an almost identical attack.

In the United States, the earliest recorded use of a VBIED was the Wall Street Bombing of 1920. Militant followers of Italian Anarchist Luigi Galleani detonated a large vehicle bomb in front of the United States Assay Office on Wall Street. The bomb was constructed from dynamite and was concealed in the back of a horse-drawn wagon.

Seven years later Andrew Kehoe, treasurer of the Bath (Mich.) Consolidated School Board, filled his car with dynamite and scrap metal shrapnel. Then he killed his wife and firebombed his farm. Thirty minutes later, the dynamite and pyrotol he had planted in the school building detonated. As the rescue there was getting underway, Kehoe drove to the school and detonated his car bomb among the survivors and rescuers.

Craig Gundry is vice president of special projects for Critical Intervention Services and program director for the S2 Safety and Intelligence Institute's anti-terrorism and WMD courses. Howard Linett is the author of "Living with Terrorism: Survival Lessons from the Streets of Jerusalem" and a member of the S2 Institute's online faculty.