Just before midnight on 3/4 August, three columns of the German Pasha I and the 4th Ottoman Army, consisting of about 8,000 men, began their attack on an outpost line held by the 1st Light Horse Brigade three and a half hours after the return of the 2nd Light Horse Brigade from their regular daytime patrol. In addition to the usual officers patrols left out overnight to monitor the enemy's positions, Chauvel decided to leave out for the night the whole of the 1st Light Horse Brigade to hold an outpost line of about 3 miles (4.8 km), covering all entrances to the sandhill plateau which formed the Romani position and which were not protected by infantry posts. A shot or two fired out in the desert to the south-east of their position put the long piquet line of the 1st and 2nd Light Horse Regiment (1st Light Horse Brigade) on alert about midnight, when the 3rd Light Horse Regiment (1st Light Horse Brigade) was called up to the front line. The Austrian, German and Ottoman advance paused after finding the gullies held by the light horsemen, but at about 01:00, a sudden heavy burst of fire along the whole front began the attack of the considerably superior Ottoman and German forces, and by 02:00 they had in many places advanced to within of the Australian line.