Violations of Norwegian neutrality

A short summary of the violations on Norwegian neutrality by Britain and Germany, and related events preceding the invasion.

date event location
The US merchant "City of Flint", taken as price by the Germans, anchors in Haugesund, and refuses to leave (by order from German government) and is thus taken by the Norwegians. The ship is released to USA and the German price crew is interned. Haugesund
Three allied merchants explodes and sinks on or nearly on Norwegian waters. At least two of them are torpedoed. The British are upset.  
British note to Norwegian government that, as the Germans uses Norwegian waters for warfare, the British will be forced to do the same. Thus British warships will operate in Norwegian waters to stop German sea traffic through Norwegian waters.  
Feb - April Numerous violation of Norwegian airspace by aircrafts from Britain and Germany.  
16/2 Altmark incident: British destroyer Cossack enters a Norwegian fjord and seizes the German ship Altmark, on its way home after a rendez vous with Graf Spee in south Atlantic. 303 prisoners are released. 7 Germans are shot dead and others are wounded. Escorting Norwegian torpedo boats are passive. Jøssingfjord
Mars German marine attaché reports to Berlin that Norway won't resist neither German nor British forces incase of an attack.  
17/3 Anti aircraft batteries in Bergen opens fire on two unidentified aircrafts (probably German) Bergen
21/3 British DD Fearless investigates German ships in Norwegian waters outside Hustadvika outside Hustadvika
22/3 British DD investigates German ships in Norwegian waters in Lindesnes-Feiesten area Lindesnes-Feiesten area
27/3 German submarine U21 runs aground on Norwegian water and is interned in Kristiansand Oddene
8/4 British destroyers lays mines on Norwegian water south of Narvik.  
8/4 German troop transport Rio de Janeiro, heading for Bergen, is sunk by a British submarine at the Norwegian south coast. Surviving soldiers tells the Norwegians that they are bound for Bergen.  
9/4 Wesertag: Germany invades Norway