 Costa <unk> argued that African soldiers were cheaper and were better able to create a relationship with the local populace , a tactic similar to the ' hearts and minds ' strategy being used by United States forces in Vietnam at the time . These Flechas units saw action in the territory at the very end stages of the conflict , following the dismissal of Kaúlza de Arriaga on the eve of the Portuguese coup in 1974 – the Carnation Revolution . The units were to continue to cause problems for the FRELIMO even after the Revolution and Portuguese withdrawal , when the country splintered into civil war . 
