Types of IEDs vary based on the type explosive used, method of assembly, and also the method of detonation. As this is restricted only by human ingenuity, the types of IEDs are infinite.
Types of explosives
The types of explosives range from explosives that are available for commercial use to those meant specifically for military use. Through the type of explosive that the non-state actors (NSA) uses, it is fairly easy to ascertain whether the NSA receives external support or not. The most commonly found commercial explosive in
is the gelatine stick that is used in the stone quarries for blasting rocks. Despite these explosives distributed only to licensed contractors, NSAs still manage to procure these either through extortion, force or by terror. The Naxals in
resort to the use of gelatine sticks for their IEDs.
Among all military explosives the most widely found in use by NSAs in
is the RDX. Even when used in small quantities, it gives a high yield with excessive destructive capability and rapid detonation. Because RDX is an exclusive military explosive and not found commercially, the use of RDX by a NSA generally points out the involvement of an outside State in the incident. Almost all the militant related IED incidents in
have used RDX. 23,334 kilograms of explosives have been seized since the start of militancy in early 1990s; 562 kgs of which have been seized only in the first 15 days of Jan 2000. The North-East militants have also come into the possession of RDX though during the initial years there was predominant use of gelatine. In addition to its high explosive potential, the RDX is also light and malleable which helps easy movement without suspicion and facilitates in effective disguise.
Types of detonation
Various detonation methods have been resorted to by NSAs in
. Detonation methods also vary from one militant group to the other. The Naxals in
use the simple fuse wire connected to batteries and closing of the circuit initiates the blast. However, in certain areas, specifically in Tada, they have also resorted to blast by pressure, the mechanism being very similar to the conventional pressure initiated mines. Despite most of their detonation methods being similar, their ingenuity lies in the assemblage of the explosive itself that makes one IED deadlier than the other.
militants are renowned for their range of detonating methods. From time pencils and electronic timers to radio waves, they have used almost all known methods of detonation. However recent trends show use of methods like timer devices that enable the militant to be as far as possible from the place of the incident so as to prevent even a chance encounter. Having surplus resources at their disposal, the militants use the most sophisticated and effective of all detonators. In recent incidents, it has been noticed that the militants have in their possession some gadget similar to the conventional 'double impulse fuse' which enables them to initiate automatically in the same IED a second blast, a few minutes or hours after the first blast. Thus the first blast essentially works as bait to lure the security forces to the vicinity, when the second blast occurs.
Types of assemblage
The type of assemblage is the crucial part of the IED as the device has to be fool proof and the container chosen disguise the deviousness of the device. The most common model is the IED in which steel pipes that are widely available in the market are used. In addition to these, the Naxals in
use steel milk cans, plastic buckets, drums, tube-light frames and mud pots. The
militants on the other hand, use almost any available container that would be deceptive and effectively mislead the security forces and public. Therefore, there have been IEDs assembled inside pressure cookers, fire extinguishers, household utensils, packets in car, bus, scooter and cycles, gas cylinders etc. Fire extinguishers, pressure cookers and gas cylinders are favoured because of the additional splinter effect they can cause due to their thick metal sheeting.
Barring the most complicated assemblies, most of the IEDs are rather simple to construct and handle, and therefore require no expertise. However, most of the groups in
seem to have received some sort of training in handling explosives at some point. The militants in North-East are alleged to have had some initial training from the LTTE (Liberation Tigers for Tamil Eelam, Sri Lanka) and the Naxals in Hyderabad are suspected have had their training from a retired army personnel from Sri Lanka; Kondapalli Seetharamaiah, leader of the Peoples War Group. The leading Naxal group in
, have however disowned any links with the LTTE. There are confirmed reports about various militant groups in
being trained in
. In each militant organization, therefore, there exists some level of expertise in explosives and bomb making.
The most simple of IEDs found in
require no expertise other than some experience. However, IEDs found in
and North-East not only need expertise and training but also access to resources that are usually not at the disposal of NSAs. Use of RDX and sophisticated detonating methods point out to support of another State, not only in training but also in material supply.