The main group was the AUC - the United Self-Defence Forces of Colombia, which officially at least has demobilised.

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The Mai Mai militias began as self-defence forces, but are now simply roving bands of thieves and thugs, often under the control of warlords of no particular politics or loyalty.

ECONOMIST: Eastern Congo

In reaction, other forces started up, local self-defence groups known as the Kamajors.

ECONOMIST: Sierra Leone

The police report describes him as a "miscreant who was part of an unlawful assembly", at which the forces had fired tear gas shells in self-defence.

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Because many Filipinos object to the return of troops from the former colonial power, American forces have not been allowed to do any fighting, except in self-defence.

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