By this stage in the war the Tank Corps had suffered greatly and there were fewer tanks available for the battle than had been deployed in the Battle of Amiens in August. Eight tanks were destroyed when they strayed into an old British minefield but the 29 September attack also highlighted the high vulnerability of tanks to strong German anti-tank measures. In one instance four heavy tanks and five medium tanks were destroyed in the space of 15 minutes by German field guns at the same location. This was during the attempt to subdue severe machine gun fire coming from the Le Catelet–Nauroy Line in the vicinity of Cabaret Wood Farm (a tank fort – see map) and showed the danger posed by German field guns to tanks operating without close infantry support (because the crew had very limited visibility and often could not see a threat which those outside the tank could see). The tanks could protect the infantry but they also needed the close cooperation of the infantry to alert them to the danger of concealed field guns. In the case of this attack, the machine gun fire was so severe that the infantry were ordered to withdraw, leaving the tanks well forward of them and prey to the German field guns.