A column of Bren Carriers of the 6th Australian Cavalry Regiment was sent south to reconnoitre the area where the Italian tanks had been reported. The column was ambushed by a party from the Babini Group with concealed anti-tank guns and machine guns; four Australians were killed and three taken prisoner. The 11th Hussars found a gap at Chaulan, south of Wadi Derna, which threatened the Babini Group and the defenders in Derna with encirclement and Bergonzoli ordered a retreat. The Italians disengaged on the night of before the garrison could be trapped; Babini Group rearguards cratered roads, planted mines, set booby-traps and managed to conduct several skilful ambushes, which slowed the British pursuit. The Italians in Libya were dependent supplies from Italy, which were moved by road and short stretches of railway. The from Tripoli to Benghazi was long, prone to flooding and attacks by the DAF now it was in range. Driving on desert tracks to avoid air attack increased vehicle wear and led to more accidents. The Babini Group had escaped destruction at Mechili on 24 January but the inferiority of the Italian tanks and that they were substantially outnumbered (possibly due to British attempts at deception with a dummy tank regiment) led to doubts that Derna was defensible. The 10th Army still had about and tanks, about half being serviceable. Rumours circulated about British intrigues in Tunisia and Algeria and the exploits of the Long Range Desert Group, Free French forces and Senussi rebels in the southern province of Fezzan, which added to Italian apprehensions about the western and southern approaches to Tripolitania. It had soon become clear to Graziani that the British were going to attempt the capture all Cyrenaica. On 1 February, he reported to Mussolini that he intended to withdraw to Sirte, where Gariboldi, the commander in Tripoli, had been ordered to prepare defences. On 3 February, after Graziani had sacked Berti, Tellera took over command in Cyrenaica, with orders to command the retreat. The Australians had caught up with the Italians west of Derna, at Giovanni Berta, on 31 January and British air reconnaissance reported indications of a general Italian withdrawal. In late January 1941, the British learned from decoded messages that the Italians were evacuating Cyrenaica through Benghazi along the . The 6th Australian Division pursued the Italians, along the coast road north of the Jebel Akhdar, with the 11th Hussars on their left flank.