An event in which no great number of troops were concerned, but which is of importance, because of the feeling which it aroused in Germany and because it was the first of a series of operations in what was practically a new theatre of the war was the Russian invasion of the very northernmost tip of East Prussia. On Thursday, the 18th of March, 1915, the Russians coming simultaneously from the north and the east across the border of Courland, moved on the Prussian city of Memel in several columns. Their troops included seven battalions of militia with six or eight guns of an old model, several squadrons of mounted men, two companies of marines, a battalion of a reserve regiment, and border defense troops from Riga and Libau, a total of some 6,000 to 10,000 men. The German Landsturm troops at the Prussian boundary fell back on Memel, not being in sufficient force to resist the advance. They were finally driven through the city and across the narrow strip of water known as the Kurische Haff to the dunes along the shore of the Baltic. The Russians burned down numerous buildings along the roads on which they approached, according to the German report, inflicting heavy damage on fifteen villages. A considerable number of the inhabitants, including women and children, were removed to Russia, and a number of civilians were killed. The troops entered the city on the evening of March 18 and took the mayor and three other men of the town as hostages. Apparently the Russian commander made some efforts to restrain his men, but plundering of stores and dwellings nevertheless occurred. On the 20th of March, 1915, the city was for a time cleared of Russian troops, but on Sunday, the 21st, other soldiers entered the town from the north. These were met by German patrols, which were followed by stronger German forces that had come up from the south to drive back the invaders. Street fighting followed, and the Russians were finally thrown out, losing about 150 dead. The Russians were pursued on March 22 and 23, 1915, and in passing through Polangen, close to the shore of the Baltic, came under the fire of German cruisers. They lost some 500 prisoners, 3 guns, 3 machine guns, and ammunition wagons. With the German troops which cleared the Russians out of Memel was the son of the emperor, Prince Joachim of Prussia.