Infantry Division (Major-General Francis Tuker) would make a night attack on around the inland end of the line, coinciding with a wide left hook manoeuvre by Montgomery. Left hook In early January 1943, a LRDG patrol had found a pass into the Jebel Dahar, which was given the name Wilder's Gap. A later patrol penetrated to the Tebaga Gap and proved that the route was practicable. The patrol demonstrated the weakness of Axis defences by going further north to Gafsa and on 2 February, made contact with the First Army, advancing from the west. Montgomery reinforced the 2nd New Zealand Division (Lieutenant-General Bernard Freyberg) and renamed it the New Zealand Corps, for an attack through the Matmata Hills via Wilder's Gap, into the Jebel Dahar, with the assembly of the force concealed from Axis reconnaissance. Staff from X Corps (Lieutenant-General Brian Horrocks) were seconded to provide adequate HQ personnel for the new New Zealand Corps, too big for one divisional staff, which caused some friction between the two generals. The New Zealand Corps advance was planned in three stages, from a night march to Wadi bel Krecheb 19 March, a second night march of to just short of the Tebaga Gap and then the capture of the entrance to the gap at first light on 21 March or as soon as possible afterwards. The corps would then advance to El Hamma, which overlooks the coast road north of Gabès. The flank of the advance was to be protected by Free French forces (General Philippe Leclerc) and the 1st King's Dragoon Guards. An attack by X Corps from Al-Hamma to Gabès would cut off the 1st Army defenders of the Mareth positions and give the New Zealand Corps the opportunity to advance up the coast to Sfax and the landing grounds on the west side of the town. The planning emphasized surprise and the ability to Axis positions. The corps had relatively few infantry and relied on its artillery to break Axis troop morale, with air support provided by fighters and bombers. A simultaneous frontal attack by XXX Corps on the Mareth Line would divide enemy attention and hamper an Axis counter-attack; the II US Corps of the First Army would advance through El Guettar to threaten Axis communications and pin down reinforcements from Sfax. Tebaga Gap The New Zealand Corps engaged the Axis troops in the Tebaga Gap on 21