The principal function of the guerrilla bands was to disrupt the supply and communication lines of the French army by intercepting the enemy's messages and by seizing convoys of supplies, money, and armaments.
O cometido principal das guerrillas era danar as liñas de comunicación e subministración do exército francés, interceptando correos e mensaxes do inimigo e apresando convois de víveres, cartos e armas.