The open discussions on an Allied expedition to northern Scandinavia, also without the consent of the neutral Scandinavian countries, and the Altmark Incident on 16 February, alarmed the "Kriegsmarine" and Germany by threatening iron ore supplies and gave strong arguments for Germany securing the Norwegian coast. Codenamed Operation "Weserübung", the German invasion of Denmark and Norway commenced on 9 April. From the 14th, Allied troops were landed in Norway, but by the end of the month, southern parts of Norway were in German hands. The fighting continued in the north until the Allies evacuated in early June in response to the German invasion of France; the Norwegian forces in mainland Norway laid down their arms at midnight on 9 June.