round the southern flank. Graziani ordered Tellera to disengage the Babini Group by next morning. Some tanks had been held back at Benghazi and work had begun on a defensive position at Sirte, to the south. In the north, on 25 January, the 2/11th Australian Battalion engaged the 60th Infantry Division "Sabratha" and the 10th Bersaglieri Regiment of the Babini Group at Derna airfield, making slow progress against determined resistance. Italian bombers and fighters flew sorties against the 2/11th Australian Battalion, as it attacked the airfield and high ground at Siret el Chreiba. The 10th Bersaglieriswept the flat ground with field artillery and machine-guns, stopping the Australian advance short of the objective. On 26 January, Graziani ordered Tellera to continue the defence of Derna and to use the Babini Group to stop an advance westwards from Mechili–Derna. Tellera requested more tanks but this was refused, until the defences of Derna began to collapse the next day. During the day, the 2/4th Australian Battalion, in the Derna–Giovanni Berta area, attacked and cut the Derna–Mechili road, a company crossing Wadi Derna during the night. On the northern edge of the wadi, a bold counter-attack, with artillery support, was made across open ground by the 10th of the Babini Group, which with reports in the morning that the group was attacking round the southern flank, deterred the Australians from continuing the advance on Derna; forty were killed and The 4th Armoured Brigade was ordered to encircle Mechili and cut the western and north-western exits, while the 7th Armoured Brigade cut the road from Mechili to Slonta but the Babini Group had retreated from Mechili during the night. During 27 January, Australian attempts to attack were met by massed artillery-fire, against which the Australian artillery were rationed to ten rounds per-gun-per-day; the 2/4th Australian Battalion repulsed another battalion-strength counter-attack. 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 and was ambushed by a party of 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 retirement. The Italians disengaged on the night of before the garrison could be trapped and Babini Group