Challe decided to start operations in the western end of the Ouarsenis range round Saida, lying to the south-east of Oran. The area was the fulcrum of Wilaya 5, previously commanded by Boumedienne, and had been firmly in rebel hands for several years, although the F.L.N. had always been weaker here than in the eastern parts of Algeria. Far less rugged than Kabylia or the Aurès, the rolling country of the Ouarsenis offered French mechanisation better prospects of driving the katibas out into the open and rounding them up; as the “softest option” it presented an ideal starting-place while Challe was still building up his Réserve Générale. … Challe kept up the pressure until April, when it was officially announced that the Ouarsenis had been cleaned up. Over 1,600 of the F.L.N. had been killed, 460 captured, and large quantities of arms and ammunition seized. Challe himself claimed that these losses amounted to fifty per cent of the A.L.N. manpower and forty to fifty per cent of its weaponry.

Horne, Alistair, A Savage War of Peace- Alge…, loc. 1010