Red strongholds fell in less than two weeks without any strong resistance. The last Red occupied town in the north was Varkaus, which the Whites seized on 21 February. In the Ostrobothnia, Central Finland, Savonia and North Karelia regions most Reds were captured, but in Lapland many were able to flee to Sweden, Norway or Soviet Russia. The Red military operations were divided into three major theaters: the Western Front (Satakunta and Häme provinces), the Middle Front (Savo province) and the Eastern Front (the Vyborg province). The northernmost area of the Western Front, located north of Tampere, was often known as the Northern Front. The Red Guard general staff worked in Helsinki, with major subordinate staffs in Tampere and Vyborg. As a major railway junction, Lahti was also an important town for the Red military. A large number of units were organized and trained there before they were sent to the eastern fronts in Savo and Karelia. The Reds launched three major offensives; in the beginning of February, 21 February and 10 March. The goal was to take the east–west railways connecting Ostrobothnia, Savonia and Karelia. From there the Reds could strike at the strongest White strongholds as well as the White capital of Vaasa. However, the offensives failed and the front line remained in the same position from early February to mid-March. On 15 March, the Whites launched their major offensive against the Reds in the northern Häme where the Red front collapsed in a couple of days. The Whites were now able to besiege Tampere, militarily the most important Red town. The Battle of Tampere was fought from 23 March to 6 April. It was the fiercest battle of the Finnish Civil War, and at the time, also the largest urban battle in the world. The Battle of Tampere ended with mass executions of surrendering Reds, of whom 10,000–11,000 were captured, and thousands fled the surrounding areas. At the same time, German troops landed on the south coast of Finland and launched their campaign to support the Whites. On 6 April, the Red Government and the Red Guard general staff left Helsinki for Vyborg. The Red units in the western provinces of Satakunta and Finland Proper were given the order to retreat to eastern Finland. The intention was to re-organize the troops behind the river Kymijoki, but the plan was never realized. Instead, the order caused a mass