at the fortress included the establishment of a 12-bed field hospital and a radio station. From 23 May the fortress came under the command of the newly established East Finnmark Naval District responsible for all RNoN units in eastern Finnmark. Air attack The fortress' sole action with the German invasion forces came on 4 June 1940. Since early May German aircraft had overflown the area without incident, but on 4 June a single Luftwaffe bomber made an attack. The bomber missed its intended target, the radio station, but damaged the church and the commandant's quarters. After expending its bomb load, the bomber flew low and strafed the area, riddling the radio hut and other buildings with bullets. In response to the attack, Corporal Olav Børve returned fire using the 65 mm Hotchkiss gun with case-shot, firing 13 rounds. After a while, the fortress' machine guns also fired back at the aircraft. With at least one of the case-shot rounds damaging the German bomber's hull it limped away from the area with a wounded navigator. Following the attack, work began on the construction of a new anti-aircraft position on the nearby Kirkeberget hill. The position was completed, but no armaments were installed before the cease-fire went into effect. Surrender and transitional period On 8 June Lieutenant Bjerkelund was informed that the fighting in Norway was coming to a close and given the opportunity to evacuate to the United Kingdom. Seizing the opportunity, Bjerkelund left for Rosyth that same day on the patrol boat Nordhav II. Bjerkelund was replaced as commander by coastal artillery lieutenant H. Johannesen later in the day. Of the ten officers and NCOs and 214 men at the fortress all but 12 of the men were demobilized on 9 June. The officers, NCOs and the dozen privates were to continue to serve until the arrival of German occupation forces. "Flag war" With the first Germans arriving only on 17 July, Vardøhus became the last armed unit under a Norwegian flag to lay down their arms during the Norwegian Campaign. This occurred on 20 July, when German soldiers took down the Norwegian flag. Between 20 and 25 July no flag flew over Vardøhus, as the Germans had ordered the Norwegian soldiers not raise the flag again. However, since the Norwegian interpreted the order as only to not raise the State flag, they instead raised the Civil ensign on 25