Plastic explosive is a puttylike explosive that can be molded into any shape. Plastic explosives combine a powerful high explosive with a moldable plasticizer, such as oil or wax. Only a powerful _detonator—_a capsule containing an easily explodable charge—can set off the high explosive. C4 is a common plastic explosive.
The United States Army developed plastic explosives during World War II (1939-1945). In the 1960’s, a French terrorist group, the Secret Army Organization (OAS), planted and detonated many plastic explosives in Algeria, seeking to prevent the country from becoming independent from French rule. The OAS attacks killed hundreds of people. Plastic explosives have remained a popular weapon among terrorists because they are powerful and easily hidden. Most plastic explosives contain chemical taggants (tracers) to make it easier for authorities to detect them.
