On a cool night in April 1999, the British Army was called out to Londonderry’s Bogside estate following reports of an unexploded bomb. Though the IRA had declared a ceasefire two years previously, splinter groups were known to still be active in the area. Local intelligence suggested that the bomb lay at the end of Abbey Street, an otherwise quiet residential road.

Despite the lateness of the hour, a crowd of locals had gathered to watch as the British ammunition technical officer (ATO) was strapped into his Kevlar and ceramic bomb disposal suit. Attempts to locate and neutralise the device remotely had failed; the only option left was a manual approach.

The ATO nodded to his corporal and started to walk, alone, down the empty road. Every couple of steps he paused and scanned the terrain, searching for any sign of the hidden explosive. From the kitchen and bedroom windows of the terraced houses that lined the cracked pavements, more locals peered out to watch his progress. The ATO tried not to think about the sniper they could be sheltering, waiting for his head to fall between their crosshair.

Brutal success

For Major Chris Hunter, the Bogside estate incident came midway through a long career of finding and neutralising improvised explosive devices (IEDs). Having worked in explosive ordinance disposal for the British Army in Northern Ireland, the UK and Iraq, as well as on counterterrorism operations in Columbia, Afghanistan and the Balkans, his life has been shaped by the ongoing battle against insurgents and their principal weapon: the homemade explosive.

Now, living in Powys, Wales, and working as a counterterrorism consultant, he regularly appears on television and radio news programmes. His opinion is also sought in the wake of major IED events, such as the recent Boston Marathon bombings.

Today, the British Army’s war on IEDs has shifted from Northern Ireland to, primarily, Iraq and Afghanistan. The former appears to have passed its IED nadir – 23,000 attacks in 2007 – but in Afghanistan, the numbers are rising; of the 444 British casualties recorded in the country to date, the overwhelming majority are a direct result of IEDs. In 2012 alone, 15,000 incidents were recorded, resulting in about 1,900 US casualties, according to Time magazine. The same article claims IEDs are responsible for around 85% of Afghan Army and police mortalities.

Even more harrowing than the brutal efficacy of these devices is the lack of a clear solution. IEDs have been successfully used around the world for decades; they were responsible for over a third of all US casualties in Vietnam. Key to this ruthless efficacy is their versatility. As soon as law enforcers find an effective neutralisation method, bomb-makers simply carry out a couple of minor alterations, or move on to a new type of device. What ensues is a perpetual game of cat and mouse.

"People are starting to realise that one IED sensor used in isolation isn’t going to work – the key is to combine several at once."

"Terrorists tend to start out with command-initiated IEDs – devices where the perpetrator has control right up to the point of detonation," explains Hunter. "We saw extensive use of these in Iraq and in Afghanistan when we first went in post-9/11. Insurgents would place an explosive charge at the side of the road, trail a command wire out to a firing point several hundred metres away, and wait until the convoy came along."

When coalition forces grew better at spotting this type of IED – lines of disturbed soil hiding command wires were a common giveaway – insurgents moved onto radio-controlled devices, activated by a mobile phone or similar appliance. Again, the army countered, this time bringing in radio-frequency jammers; specially equipped personnel capable of blocking the radio signals used to trigger explosives. After a brief battle for the airwaves in which the jammers soon gained the upper hand, the bomb-makers again switched tactics. Victim-operated devices, also known as booby-traps, began to proliferate.

Hunter describes these latest devices as "extremely crude… they’re right at the beginning of the technological sophistication spectrum". Typically consisting of nothing more than a battery pack, explosive charge, household wires and two pressure plates that form a circuit when pushed together by a soldier’s foot or vehicle wheel, it is a painfully accurate description. Painful because, despite the billions of pounds spent on training and IED-detection technology, bombs that cost pennies to produce with a design that dates back to the American Civil War are still a major stumbling block for today’s coalition forces.

Promising developments

Though still far from perfect, IED-detection and clearance methods are steadily improving for soldiers on the ground. Whereas the first vehicles used were typically unarmoured and had limited sensory capabilities, the latest models, such as the Husky, are heavily protected and feature high-sensitivity, low-metal content detectors, as well as ground-penetrating radar and thermal-vision equipment.

"In Afghanistan, IED attack numbers are rising; of the 444 British casualties recorded, the overwhelming majority are a direct result of IEDs."

There have also been promising developments in the use of unmanned aerial vehicles and the field of laser-induced mass spectroscopy, where a beam fired at a potential IED provides information on its chemical composition and therefore what type of bomb, if any, it is. Currently a cumbersome vehicle-mounted tool, technological advancements should soon see these devices transformed into a more practical hand-held design.

"What we’re starting to see is a more intelligent response to IED-detection methods," says Hunter. "People are beginning to realise that one sensor used in isolation isn’t going to work – the key is to combine several at once.

"It’s because of this smarter approach, along with better technology and improved troop tactics, that we’ve seen an extensive increase in the number of devices detected in Afghanistan in recent years."

The bigger picture

Yet while improvements to IED-detection methods can save soldiers’ lives, the real key to defeating the bomb-makers lies in attacking and, ultimately, bringing down support networks. This can involve targeting training facilities, recruiters, financiers and other structural elements. But by far the most effective approach – as in conventional warfare – is to disrupt supply chains.

By analysing forensic and DNA evidence from devices, as well as design idiosyncrasies and individual bomb components, army intelligence officers are able to build up a picture of IED procurement and manufacturing networks. It was through such analysis that the infamous shoe bombers Richard Reid and Saajid Badat were discovered to be secret collaborators when they had claimed to be acting as lone wolves; the detonating chords and fuses the pair had used were both cut from the same length of wire.

"Details such as batch numbers can also be used to trace components back to the manufacturer," Hunter adds. "We’re then sometimes able to identify the shop or store where the parts were sold. CCTV can be analysed, and it’s possible, in some cases, to identify the bomb-maker or procurer who physically purchased those components."

Focusing on these sorts of commercial details has led to the discovery and overturning of major procurement networks in the past. In 2005, an unexploded Iranian-made IED was found to contain US computer circuits. This should have been impossible, as the country has long had a trade embargo with Iran.

Using the IED’s component serial numbers and sales records, intelligence officers, including Hunter, who was then working at the UK Ministry of Defence, were able to uncover a huge illegal operation: Dubai firm Mayrow General Trading was purchasing large amounts of electronics components from the US, including field-programmable gate arrays, integrated circuits, global positioning systems, field communicators and microcontrollers – exactly the same types of items found in Iraqi and Afghan IEDs. Mayrow and its affiliate companies were sending these components onto Iran to be turned into IEDs, thus bypassing the US trade embargo.

Eight individuals and the same number of corporations have since been indicted by the US district court of southern Florida.

Measure and countermeasure

Though international intelligence sharing is vital to bringing down IED procurement networks such as Mayrow, national security concerns often prevent the free exchange of counterterrorism information. The US is one of a select few to make an effort to declassify and share data wherever possible. Most other countries, however, are less obliging.

"IEDs are the perfect weapon for insurgents looking to fight back against financially and technologically superior military powers."

"The whole information-swapping service is a long way from perfect," says Hunter. "It can often take up to 18 months to bring all the intelligence together and get the buy-in from every decision-maker to create an effective IED countermeasure.

"Then in no time – I’ve known it to be as little as six days – the insurgents come up with a new device. And we have to go through the whole procurement chain again to bring in a new countermeasure, which can take another 18 months. The whole process just repeats itself."

It is this endless race of measure-countermeasure between bomb-makers and law enforcers that lies at the heart of the IED problem. Cheap and easy to manufacture, and highly versatile, they are the perfect weapon for insurgents of limited means looking to fight back against financially and technologically superior military powers.

And with national authorities standing little real chance of either halting production or significantly reducing efficacy, IEDs look set to remain a serious threat to soldiers and civilians for the foreseeable future.

Back on the Bogside

Back on the Bogside estate, Hunter continues alone down Abbey Street.

Suddenly, a blinding flash of white light fills his vision. The infrared camera-equipped helicopter called in to search for threats has found a suspect sniper and is shining its spotlight on the area; a derelict building directly in front of Hunter.

Shouts break out on both sides of the street. For Hunter, the loudest is the cry of his corporal, bawling at him to turn around, and run.

Both men got away in the end; Hunter to the safety of his troop, the suspect sniper into the Bogside estate’s maze of alleys and side streets.

The bomb itself had never existed. The whole scenario had been engineered by an IRA splinter group with the sole aim of assassinating Hunter.