A foothold was established on Aubers Ridge on 17 October and French cavalry captured Fromelles. On 18 October, the German XIII Corps arrived, reinforced the VII Corps and gradually forced the British II Corps to a halt. On 19 October, parties of British infantry and French cavalry captured the village of Le Pilly, which later was recaptured by the Germans. The fresh German 13th and 14th divisions arrived and counter-attacked the II Corps front. By 21 October, II Corps was ordered to dig in from the canal near Givenchy, to Violaines, Illies, Herlies and Riez, while offensive operations continued to the north. The Lahore Division of the Indian Corps arrived and the British repulsed German attacks until early November, when both sides concentrated their resources on the First Battle of Ypres and the battle at La Bassée ended. Battle of Messines, 12 October – 2 November The III Corps reached St. Omer and Hazebrouck from then advanced eastwards towards Lille. The British cavalry advanced and found the Germans dug in on Mont des Cats and at Flêtre on the road from Cassel to Bailleul. The 3rd Cavalry Brigade attacked Mont des Cats and occupied Mt. Noir, north of Bailleul. On 14 October, the cavalry advanced north-eastwards, occupied Dranoutre and Kemmel against slight opposition, then reached a line from Dranoutre to Wytschaete (Wijtschate), linking with the 3rd Cavalry Division of IV Corps, which had been operating in Belgium since early October. On 15 October, Estaires was captured by French cavalry but the Germans prevented an advance beyond Comines, west of Menin (Menen), where German troops had arrived during the night. A foothold was gained at Warneton and German outposts west of the Ypres–Comines canal were pushed back to the far side. By 16 October, the Cavalry Corps and the 3rd Cavalry Division held the Lys river from Armentières to Comines and the Comines canal to Ypres. The BEF was ordered to make a general advance on 16 October, as the German forces were falling back. The cavalry were ordered to cross the Lys between Armentières and Menin as the III Corps advanced north-east to gain touch with the 7th Division near Ypres. Fog grounded Royal Flying Corps (RFC) reconnaissance aircraft and made artillery observation impossible. The Lys was wide and deep and flanked by water meadows. The banks were cut by boggy streams and dykes, which kept the cavalry on the