Flechas units were created and employed in Angola, during the Portuguese Colonial War, under the command of the PIDE (renamed DGS in 1969). Despite being a paramilitary police force, they were thus a police unit, not being under military command as the remaining special force.
Flechas were organized as platoon-sized units consisting of local tribesmen and rebel defectors who specialised in black operation, clandestine operation, counterinsurgency, covert operation, pseudo-operations, special reconnaissance, tracking, and urban warfare.