Nevertheless, the Serbians in Belgrade gave a good account of themselves. There were stationed there the big naval guns, 4.7-inch and 6-inch, sent into the country by Great Britain, France, and Russia, and served by their expert gunners. For several days the foreign gunners, under command of Rear Admiral Troubridge, swept the broad surface of the Danube and the Save, sinking two of the enemy's gunboats that happened to come within range. On October 5, 1915, the German fire on Belgrade intensified and became terrific. They no longer satisfied themselves with pouring their deadly fire on the fortress of Belgrade and the neighboring positions at Zamar, but they began a systematic bombardment of the city itself, hurling vast quantities of inflammatory bombs, as though they meant to burn down every building before attempting to take it. Into the suburbs beyond, through which ran the highways leading into the interior, they rained a curtain of fire which made flight for the inhabitants almost impossible. On October 6, 1915, the Austro-German forces finally managed to effect a crossing which the Serbians were not able to repulse; at several points they landed on the opposite bank, including Belgrade itself. The first attempts had been made at Jarak, Podgorska Island, and Zabrez, and had been driven back again and again, but this time the enemy put such energy behind his efforts that eventually the Serbians were no longer able to drive him back. Gypsy Island, too, a short distance from Belgrade, was captured, whence a landing was made under the Lower Fortress and on the Danube Quay in the city itself. In the first attempt all the Austrians or Germans who landed under the Lower Fortress were either killed or captured. Finally the invaders established themselves permanently on the quay. During that day the fighting was of a bloodier character than had as yet taken place. Next day, October 7, 1915, the Austro-Germans pushed on to further success; their big guns raked the river shore up and down and tore down all defensive works, making them untenable for the defenders. And on the day following, October 8, 1915, the Austro-Hungarian troops of Koevess penetrated into the northern sections of the city, taking the citadel by storm. At the same time a German contingent, attached to Koevess's command, landed west of the city and took the heights in that section, fighting its way to the Konak and finally to the Royal Palace, in the center of the city, over which they hoisted the German and Austrian flags. Though there was still much to do, Belgrade was now practically in their hands.