The first French contingents were deployed north of N'Djamena at points on the two possible routes of advance on the capital. Fighter aircraft and antitank helicopters were dispatched to Chad to discourage an attack on N'Djamena. As the buildup proceeded, forward positions were established roughly along the 15th parallel from Mao in the west to Abéché in the east (the so-called "Red Line"), which the French tried to maintain as the line separating the combatants. This force eventually rose to become the largest expeditionary force ever assembled by France in Africa since the Algerian War, reaching 3,500 troops and several squadrons of Jaguar fighter-bombers.