After the Allied victory at the Battle of Dobro Pole near Salonika and the British victory at the Battle of Megiddo , the army in Caucasus was the only source for Ottoman reinforcements and had to give up more and more divisions, that eventually ended offensive operations in the theatre. After resting, the Ottoman army in Caucasus advanced with the 15th Division northwards along the Caspian coast to Derbent but were held up on 7 October by troops supported by naval gunfire from the Bolshevik fleet. The Ottomans attacked again from and the 15th Division reached Petrovsk on 28 October. After several attacks the city fell on 8 November, in the last Ottoman offensive operation of the war and marked the northern limit of the Ottoman advance into the Caucasus Mountains.