On 15 September 1918, a combined force of Serbian, French and Greek troops attacked the Bulgarian-held trenches in Dobro Pole ("Good Field"). The assault and the preceding artillery preparation had devastating effects on Bulgarian morale, eventually leading to mass desertions. On September 18, a second Entente formation assaulted the Bulgarian positions in the vicinity of Lake Doiran. Effectively employing machine gun and artillery fire the Bulgarians managed to stall the Allied advance on the Doiran sector. However the collapse of the front at Dobro Pole forced the Bulgarians to withdraw from Doiran. The Allies pursued the German 11th Army and the Bulgarian 1st Army, while pushing deeper into Vardar Macedonia. At 17:30 p.m. on 22 September 1918, the 35th Italian Division assaulted Hill 1050, seizing it from the 302nd Division and taking 150 prisoners. Fighting took place in Kanatlarci and along the Monastir–Prilep road, in Cepik, Kalabak and Topolčani as the Allies continued to advance towards Prilep. At 14:00 p.m. on 23 September, General Louis Franchet d'Espèrey announced that the initial plan of the operation was to be modified. The Italians were ordered to strike Kičevo with the aim of preventing the enemy forces stationed at Monastir from reaching the railroad hub in Uskub, the 11th Colonial French Division was instead tasked with securing Prilep. Half an hour later the French entered Prilep, to the east Franco–Serbian columns marched on Štip, Veles, Brod and through the Peristeri mountain range. By 29 September, the Allies had captured the former headquarters of Uskub, thus endangering the remnants of the 11th Army.