The attack on Tobruk started on 20 June 1942

A small outpost had been kept outside of Tobruk at Acroma. These troops were withdrawn on 18 June 1942. A reconnaissance force of South African armoured cars and small columns continued to screen the defenses at Tobruk. Rommel had asked Field-Marshal Kesselring for a concentrated air attack at the time of the assault on Tobruk. Kesselring wanted to finish with Tobruk so they could concentrate on Malta, so he was a willing accomplice. The orders for the attack were given on 18 June. The attack would commence on 20 June. The Axis bombers began their attack at 5:20 in the morning. German troops moved forward to start the attack at 7am. Crossings were constructed over the tank ditch and the tanks moved forward at 7:45. The leading tanks of the 15th Panzer Division actually crossed the ditch at 8:30. They were followed by those of the 21st Panzer Division, which had been slowed by mines. This is based on the account in Vol.III of the Official History.