Command Operated Explosive Devices

An article authored by ISDA Member William Clark

Command operated explosive devices are being used successfully worldwide. These devices were brought to the forefront by the Boston Marathon bombing.  This incident demonstrated that these types of explosive devices can be used effectively in the United States. The command operated device can be detonated by either remote control or wired directly, and requires the bomber to keep the device in his sight, while waiting for the intended target. The bomber picks the place and time the device will be detonated.

Command Operated Explosive Devices

Example of one type of command operated device – this device is controlled by a direct wire which is underground and runs from the bombers position to the IED.

Cell phones, remote car starters and door openers, car alarms, portable two way radios, wireless doorbell systems, can and have been used effectively in remote controlled – command operated devices. This type of device can be hidden in or alongside a roadway, as a package, backpack, or attached directly to a vehicle. However, some devices seen in the U.S., use components from radio controlled toy cars which are easily obtained.

This article will focus on the radio controlled type device. As we know from the Boston Marathon bombing, these types of devices were hidden inside backpacks and left in the spectator’s located near the finish line. These devices were constructed from pressure cookers, filled with low explosive powder, obtained from legal fireworks, and shrapnel. The initiators used were fashioned from Christmas light bulbs and possibly filled with a peroxide based explosive. The switches for the devices came from remote controlled toy cars. Construction of these types of devices can be found in the al-Qaeda magazine “Inspire”.

The basic components for this type of device are; the hand controller switch that will operate the device and the internal components (circuit board) from the car, which will be attached and connected directly to the device. The battery used inside the car will supply electrical power to the detonator or igniter. The only other required components are a container, detonator or igniter, and explosive filler.

The hand held control device (transmitter) sends a signal to the receiver (car) which consists of a circuit board by radio frequency. The operating ranges for these cars are up to 200 yards. Battery time is important, because once the device is switched “on”, energy will be consumed, thus, limiting the life of the battery.

When military and law enforcement units suspect that radio controlled devices are a risk, they deploy various types of jamming devices (electronic counter measures) that interrupt the radio frequency between the controller (switch) and the explosive device, thus preventing detonation. These jamming devices can be portable or fixed to a vehicle.

Case Study:


September 21, 2011 in Monroe, Michigan – a pipe bomb had been attached to the underside the burning car; the explosion took place while the car was being driven, followed by the fire. The explosion injured the three occupants of the car.


The photo shows a replica of the device used in the Monroe, Michigan bombing. A toy car remote controller with the circuit board from the toy and battery are attracted to the pipe bomb. This is another type of command operated device. The bomber detonates this type of device at his will, when the victim is within the “kill zone”.


Surveillance detection techniques are the key to early recognition of the bombers presence. Since the bomber will keep the device within their line of sight to observe when the victim is within the “kill zone”, he would be observed in the area for extended periods of time just “waiting”. If the suspect is noted just “standing around” he would likely be carrying some type of a backpack, to conceal the large switch from the toy car contoller. Also, basic vehicle security procedures for parked vehicles will also prevent this type of device from being successful.

About the Author

Bill is an ISDA, QCC member and a retired law enforcement officer. He is currently employed by Rimkus Consulting Group, Inc. Richmond, VA. After retirement, he was employed as a contractor for the Department of Defense as an explosives instructor. He is also an instructor for the Department of Homeland Security Courses – Prevention and Response to a Suicide Bomber and Incident Response to a Terrorist Bombing. He has recently worked as a security driving and firearms instructor. He can be reached at [email protected].

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