There are a number of ways to subclassify IEDs: by delivery means, by activation means, or by usage
(see Figure 3-2).
Figure 3-2. Subclassification.
2. Arson. Although not a tactic used by all terrorist groups, arson is a powerful weapon of destruction
and disruption. Public utilities, commercial premises, and political buildings are frequent targets. A
popular method of starting fires is by using time-delayed incendiary devices which are comparatively
cheap and easy to make, easily concealed, and difficult to detect once planted.