Carthaginian armies were nearly always composed of foreigners; citizens only served in the army if there was a direct threat to the city of Carthage. The majority of these foreigners were from North Africa. Libyans provided close-order infantry equipped with large shields, helmets, short swords and long thrusting spears; as well as close-order shock cavalry carrying spearsboth were noted for their discipline and staying power. Numidians provided light cavalry who threw javelins from a distance and avoided close combat, and javelin-armed light infantry skirmishers. Both Spain and Gaul provided experienced infantry; unarmoured troops who would charge ferociously, but had a reputation for breaking off if combat was protracted. The close-order Libyan infantry, and citizen militia when present, would fight in a tightly-packed formation known as a phalanx. Two thousand slingers were recruited from the Balearic Islands. Sicilians and Italians had also joined up during the war to fill the ranks. The Carthaginians frequently employed war elephants; North Africa had indigenous African forest elephants at the time. Roman sources refer to these foreign fighters derogatively as "mercenaries", but Goldsworthy describes this as "a gross oversimplification". They served under a variety of arrangements; for example, some were the regular troops of allied cities or kingdoms seconded to Carthage as part of formal arrangements.