The Australian Army first saw action in Operation Compass, the successful Commonwealth offensive in North Africa which was conducted between December 1940 and February 1941. Although the 6th Division was not fully equipped, it had completed its training and on 14 December, it relieved the 4th Indian Division. Given the task of capturing Italian fortresses bypassed by the British 7th Armoured Division during its advance, on 3 January, the division went into action at Bardia. Although the fortress was manned by a larger force, the Australian infantry quickly penetrated the Italian defensive lines with the support of British tanks and artillery. The majority of the defenders surrendered on 5 January and the Australians took 40,000 prisoners. The 6th Division followed up this success by assaulting the fortress of Tobruk on 21 January, securing it the next day and taking 25,000 Italians prisoner. After this, the Australians pushed west along the coast road to Cyrenaica and captured Benghazi on 4 February. Later that month, the 6th Division was withdrawn for deployment to Greece and was replaced by the untested 9th Division, which took up garrison duties in Cyrenaica.