The infantry assault by the 29th Division on 1 July 1916 was preceded ten minutes earlier by a mine explosion under the fortified Hawthorn Ridge Redoubt. The explosion of the Hawthorn Mine underneath the German lines destroyed a major enemy strong point but also served to alert the German forces to the imminent attack. Following the explosion, troops of the 119th (Reserve) Infantry Regiment moved from their dugouts into the firing line, even preventing the British from taking control of the crater as they had planned. When the assault finally began, the troops from the 86th and 87th Brigade of the 29th Division were quickly stopped. With the exception of the 1st Battalion of the Royal Inniskilling Fusiliers on the right flank, the initial assault foundered in No Man's Land at and short of the German barbed wire. At divisional headquarters, Major-General Beauvoir De Lisle and his staff were trying to unravel the numerous and confusing messages coming back from observation posts, contact aircraft and the two leading brigades. There were indications that some troops had broken into and gone beyond the German first line. In an effort to exploit the perceived break in the German line he ordered the 88th Brigade, which was in reserve, to send forward two battalions to support attack.