Signs of war

Daylight on April 9, the German air force hit the Oscarsborg with severe 9-hours bombardment. Anti-aircraft force in Oscarsborg possessed only two Swedish 40 mm Bofors L/60 and seven 7.92 mm machine guns Colt M/29 on batteries of Håøya and Seiersten, some of which soon were broken down. A total more than five hundred 100- and 200-kg bombs were dropped to Oscarsborg. The garrison had taken refuge in the dungeons and had no losses.
In the picture tracks of German bombing on 28 cm guns are seen.