the Central Powers’ artillery opened harassing fire, zeroing in their guns. The following morning at 0600 they began a sustained bombardment from field guns to heavy howitzers, at 0900 the mortars joined in. The huge mortar shells were especially terrifying, their blast killed men tens of meters from the explosion. The Russian fortifications were "... more ditches than trenches." According to François, "The mortars began their destructive work. The ground trembled, hell seemed to be let loose." According to Arz, "Our tension peaked as the infantry set off from their assault positions precisely at 10 o'clock." Mackensen had already defined "lines that should be reached in a uniform and if possible simultaneous manner, without preventing the troops from collectively moving on to secure the next sector where possible." After the first day, Mackensen reported, So far, everything is proceeding well," and on 3 May he reported 12,000 prisoners had been captured. François reported, "Gorlice was almost demolished; the section of the town that had been fighting resembled a sea of ruins." Mackensen then issued orders for the advance upon the River Wisłoka as the next objective, which constituted the Russian third and final line of defense. In the meantime, Russian reserves in the form of the III Caucasian Corps, could not provide relief for at least a day. Yet, since this corps was committed to battle piecemeal, they proved of limited value in hindering the German advance. Radko Dimitriev quickly sent two divisions to stem the Austro-German breakthrough, but they were utterly annihilated before they could even report back to headquarters. From the Russian point of view, both divisions simply disappeared from the map. On 3 May the Grand Duke Nicholas was sufficiently concerned to provide three additional divisions and to authorize a limited withdrawal. The Russian XII Corps near the Dukla Pass began its withdrawal, as did the XXIV Corps near Nowy Żmigród, signifying Russian control of the Carpathians was becoming ever more tenuous. The Korps Emmich 20th Infantry Division, Korps Kneussl was renamed after Otto von Emmich took over command, captured Nowy Żmigród. Using an intact bridge over the Wisłoka, this division was able to advance to Wietrzno. By 5 May the attackers were through the three trench lines that had opposed them, by 9 May they had reached all assigned objectives. Grand Duke Nicholas permitted a limited withdrawal, but rejected advice to construct a well fortified position