U.S. Troops Faced Pressure Cooker IEDs in Iraq and Afghanistan

The crude explosive devices used against runners and spectators at the Boston Marathon were similar to the kitchen pot bombs aimed at U.S.  troops on foot patrol in Afghanistan, law enforcement and Congressional officials said Tuesday.

For nearly 10 years, presidential directives, Homeland Security Department reports and local law enforcement officials have warned of the eventual threat within the U.S. of “pressure cooker” bombs developed by terrorists in Afghanistan and Iraq.

After briefings from law enforcement and U.S. intelligence officials, Rep. Randy McCaul (R-Tex.) said that the two devices which detonated in Boston appeared to be “pressure cooker” bombs. Law enforcement officials later confirmed that the investigation was proceeding on the basis that the devices were “pressure cooker” bombs.

But Rick DesLaurier, the FBI’s special agent in charge in Boston, stressed that “the investigation is in its infancy.” At a news conference in Boston, DesLauriers said there had thus far been “no claims of responsibility and the range of suspects and motives is wide open.”

DesLauriers asked the public to contact authorities if they knew anyone who had recently expressed a special “interest in research in how to create explosive devices.”

In Afghanistan, Taliban operatives who lacked the wherewithal or expertise to build “improvised explosive devices” capable of destroying the huge, V-shaped hull MRAPs (Mine Resistant Ambush Protected vehicles) turned to “pressure cooker” bombs as anti-personnel devices. They would be placed along paths expected to be used by U.S. troops on foot patrol.

In the summer of 2011, explosives specialists from the 2nd Battalion, Eighth Marines, showed several of the devices they had found and defused to an embedded reporter. One of the devices had even been placed in a tree, the specialists said.

The terrorists would take a simple kitchen pot, a pressure cooker was preferred, pack it with ammonium nitrate and metal filings, nails and even rocks to increase the lethality, and rig the device to detonate by wire or by a remote device, sometimes a garage door opener.

When triggered, the blast would seek the path of least resistance and most of the force and the debris would blow out the top of the pressure cooker, in effect acting much like a military “shaped” charge that concentrates  the force of an anti-tank shell.

As far back as 2004, a Homeland Security Department memo warned of the pressure cooker bomb threat, calling it “a technique commonly taught in Afghan terrorist training camps.”

“Typically, these bombs are made by placing TNT or other explosives in a pressure cooker and attaching a blasting cap at the top of the pressure cooker,” the memo said.

The attraction of the pressure cooker bomb for the terrorist is that they are cheap, relatively easy to make, and lethal.

A presidential directive on homeland security in 2007 warned that “The threat of explosive attacks in the United States is of great concern considering terrorists’ability to make, obtain, and use explosives, the ready availability of components used in IED construction, the relative technological ease with which an IED can be fashioned, and the nature of our free society.”

In 2010, a joint FBI and Homeland Securty intelligence report issued in 2010 warned that “Placed carefully, such devices provide little or no indication of an impending attack.”

Two years ago, “Inspire,” the online magazine of Al Qaeda in the Arabian, published an article on how to make a pressure cooker bomb. The title of the article was “How To Make A Bomb In The Kitchen Of Your Mom.”

About the Author

Richard Sisk
Richard Sisk is a reporter for Military.com. He can be reached at richard.sisk@military.com.
  • Nadnerbus

    Perhaps mandatory background checks and a waiting period for crock pots is in order. We don’t want these instruments of war falling into the wrong hands, right?

  • philcool

    What surprised me is that nobody removed the trashcans before the marathon was held

    • blight_

      We’re still not sure how they stashed the bomb. A pressure cooker in a trash can will probably mitigate blast and fragments. One in a backpack, won’t.

    • Musson

      The Daily Mail has pictures taken of one of the bombs before it exploded.
      It sure looks like a big bag of trash sitting right in front of the moveable fence section. It was pretty freakin’ obvious.

      • blight_

        We’re paying tons for paramilitaries to look for guys with dishdashas screaming Allahu Ackbar, but they just leave a bag of trash and walk away. Boom.

        Ban trash bags?

  • Sergi

    ETA, the terrorist group in Spain, has used this method, from at least 1986, that is the first entry on google… http://blogs.libertaddigital.com/in-memoriam/masa… (Translation: http://www.google.com/translate?hl=en&ie=UTF8….

    I don´t see why this is news…

  • blight_

    I was wondering if they were using bombs under pressure, or just using the pressure cooker to hold the bomb.

    The article notes that the top may blow off: but if this is so, then it limits the effective range of such a device, unless you prop it pointed at a target (which is probably what happened).

  • FoolKiller

    “in effect acting much like a military ‘shaped’ charge that concentrates the force of an anti-tank shell.”
    No. This was a directional explosion with shrapnel, much like a homemade claymore. A truly “shaped” charge focuses the force of the explosion itself, or intensely hot metal vapor produced as a byproduct of the explosion, to penetrate armor. No shrapnel is involved in a true shaped charge. In any event, shrapnel would be useless against a tank.


    My question is who will take responsibility for this? This doesn’t feel like an Al Qaeda attack. Also, is this connected to the poisoned letter sent to Senator Wicker from Mississippi? If so, this could just be the beginning of a mass attack of these terrorists.

  • Sanjay
  • HeavyArrow

    Personally I think we shouldn’t be giving the guy who did it (Even if we don’t know who) the media coverage that we always do whenever something like this happens, they WANT the attention. Focus on the survivors and the good things that people did to help those wounded in the detonation.

  • STemplar

    Based on the injuries I don’t think the devices were placed in trash cans. Far too many wounded and mostly lower leg injuries. I think the bags were just left on the ground.

  • Rosalee

    Frankly not surprised…………….dad talked about mines and IEDs in Vietnam..
    planted conveniently for our troops……..and in some cases when they would
    stop to hand out whatever to little children, much like in some stories I have heard
    about Iraq and Afghanistan.

    I wonder now if the bombs in Boston were put together nearer the site?
    It would seem that they might be a bit ‘dangerous’ if they were hustled too much
    to the site………just speculating……..

  • Scanlon

    Let the disinformation and misinformation begin.

  • tim hooey



    Well, all I can say is that the police just got that son of gun. Glad that manhunt is over.