the Battle of Komarów and the Battle of Gnila Lipa began in Poland. A naval action took place off Åland and a German cruiser ran aground and was intercepted by a Russian squadron. On 3 September, Lemberg was captured by the Russian army and the Battle of Rawa (Battle of Tarnavka began in Galicia. The First Battle of the Masurian Lakes began and on 8 September, the Austro-Hungarian army commenced the Second Invasion of Serbia, leading to the Battle of Drina The Second Battle of Lemberg began and on 11 September, Austrian forces in Galicia retreated. The Battle of the Masurian Lakes ended on 15 September and Czernowitz in Bukovina was taken by the Russian army. On 17 September, Serbian forces in Syrmia were withdrawn and Semlin evacuated, as the Battle of the Drina ended. Next day General Paul von Hindenburg was appointed (, Commander-in-Chief of German Armies in the Eastern Theatre). On 21 September, Jaroslaw in Galicia was taken by the Russian army. On 24 September, Przemyśl was isolated by Russian forces, beginning the First Siege as Russian forces conducted the First Invasion of North Hungary Military operations began on the Niemen but German attacks were suspended on 29 September. The retreat of Austro-Hungarian forces in Galicia ended and Maramaros-Sziget was captured by the Russian army; an Austro-Hungarian counter-offensive began on 4 October and Maramaros-Sziget was retaken. On 9 October, the First German Offensive against Warsaw began with the battles of Warsaw and Ivangorod As the situation on the eastern front deteriorated in September, the new German high command under General Falkenhayn attempted to retrieve the situation in France and inflict a decisive defeat. Tactical developments Operations in Belgium, August–October 1914 On 2 August 1914, the Belgian government refused the passage of German troops through Belgium to France and on the night of the Belgian General Staff ordered the Third Division to Liège to obstruct a German advance. Covered by the Third Division, the Liège fortress garrison, a screen of the Cavalry Division and detachments from Liège and Namur, the rest of the Belgian field army closed up to the river Gete by 4 August, covering central and western Belgium and the communications towards Antwerp. The German invasion began on 4 August, when an advanced force of six German brigades from the 1st, 2nd and 3rd Armies, crossed the German-Belgian border. Belgian resistance and German fear of , led