Explainer: What you need to know about IED attacks

Wednesday March 18 2020

Last week’s terror attack that left 11 General Service Unit (GSU) officers dead in Garissa has put in sharp focus the rising use of improvised explosive devices (IEDs) by Al-Shabaab against security officers along the Kenya-Somalia border.

Every year, thousands of people across the world die a result of IED attacks.

So, what is an IED? What is it made of? How does it work? And what is its extent of damage?

Foremost, the term IED came into common usage during the Iraq war, which started in 2003 and involved US troops.

During the war, many US soldiers were killed when their vehicles rode over these devices.



According to the US Homeland Security, an IED is a ‘‘homemade bomb or a destructive device meant to destroy, incapacitate, harass, or distract’’ the target.

These devices contain destructive, lethal, noxious, pyrotechnic or incendiary chemicals.

Homeland Security further states that these devices are used by criminals, vandals, terrorists, suicide bombers and insurgents, as is the case with Al-Shabaab.

IEDs come in many forms— from small simplistic pipe bombs to more sophisticated devices capable of causing mass destruction and loss of life.

Owing to their simplicity, IEDs can be carried and launched by hand, delivered in a vehicle, concealed by the roadside or even delivered as a package.

Terrorists often leave them in buildings that experience heavy human traffic such as malls, theatres and churches, on aircraft, on the streets and even in stadia.

The aim is to inflict maximum damage to as many people as possible once the bomb goes off.


Terrorists in northern Kenya have been burying them on road routinely used by Kenya Defence Forces personnel or police officers on patrol.

Last Saturday’s tragedy was such a case.

How are IEDs made and what types exist?

American bomb expert and director of Explosives Technologies at DSA Detection John Howell says IEDs are categorised based on five main components namely:

  • Source of power
  • Switch
  • Detonator or initiator
  • Wire
  • Type of explosive (chemical) used

Command-detonated device or radio-controlled IED (RCIED) are the most commonly used IEDs in the world today. Use of cell phones or a radio controlled (RC) type firing circuit are in mass use. Over time, radio control cars, car alarms and other types of RC transmitters have been used along with any type of cell phone.

So why are IEDs used?

A research paper by US National Research Council titled Countering the Effectiveness of Improvised Explosive Devices says that throughout history, these weapons have been used with varying effectiveness.

‘‘...groups have resorted to the use of IEDs to advance a particular cause or wear down an adversary,” the paper reads.

“IEDs are used by terrorists to strike soft targets and by insurgents as weapons against a stronger enemy.”

IEDs are also relatively cheap owing to the low cost of materials used to make them.

The fact that they can achieve both strategic and tactical results makes them particularly lethal.


United Nations Office for Disarmament Affairs (UNODA) describes the impact of use of IEDs on security and stability of affected regions as dire and profound.

According to the UN body, thousands of people, including civilians, military personnel and humanitarian workers and peacekeepers are killed by IEDs every year.

The devices also inflict injuries, cause dire psychological harm and spread fear and disruption across affected communities, the UN says.

‘‘IED attacks not only hinder the political, social and economic development of a country, they also block life-saving humanitarian aid,’’ UNODA says.

IEDs have also become the primary weapon for non-state armed groups across many conflict zones, it says.

As of 2014, IED incidents had occurred in 66 countries and territories including in Africa, the Americas, Asia, and Europe.

During this period, eight countries suffered more than 1,000 civilian casualties.

In the last 10 years, more than 100,000 people have been killed in IED attacks, with civilians accounting for three-quarters of the casualties.

In Afghanistan, for instance, IEDs kill 10 times more civilians than landmines.

Hundreds of aid workers have also died from IED attacks in the last decade.

Can use of IEDs be controlled?

UNODA notes that most IEDs are produced entirely outside of government oversight ‘‘due to their specific nature as a tool of asymmetric warfare’’.

‘‘Combating their covert, rough-and-ready manufacture is a particular challenge,’’ the UN says, adding that a comprehensive approach to addressing the rising threat of IEDs has been lacking.

The body says there is only ‘‘piecemeal international cooperation against the rapid and widespread transfer of knowledge on IED design’’ and that there is little work on controlling commercial components coupled with absence of sustained attention to victim assistance.