with estimates of intended position during the night and next day with orders to join forthwith. The minelayers reached Vestfjorden without incident and by 05:26 on Monday 8 April, 234 mines were laid as planned.
The Norwegian auxiliary Syrian was at anchor on the landward side of Vestfjorden that morning. The weather was poor with large swells and patches of fog. At 04:20, eight destroyers were observed well inside Norwegian territory. A little later, some of them were seen to commence dropping what appeared to be mines from their sterns. Kaptein Bjarne Kaaveland sent a preliminary radio signal to SDD3 in Tromsø while weighing anchor and headed for the lead destroyer. The signal ‘Neutral Territory’ was hoisted at the masthead while the signal ‘Protest. Leave Norwegian territory’ was repeatedly flashed by lamp. The destroyer, already identified as the British HMS Hunter from the pennant H35 on her side, answered by hoisting ‘Minefield ahead. Stop for instructions’ and replied by lamp ‘Will not leave territory’. Closing, a boat was lowered from Hunter and a British officer came across. He informed them that mines were being laid and handed Kaptein Kaaveland a map with the co-ordinates. The officer added that two destroyers would stay with the minefield to warn approaching ships for forty-eight hours, and requested Syrian to assist. Several merchant vessels had already been stopped and the traffic along the coast was for all practical purposes severed. While the officer from Hunter was still onboard Syrian, one of the other destroyers moved to the north side of the alleged field while the rest headed south-westwards, out of sight in the mist.
HMS Impulsive of 20th Destroyer Flotilla. To facilitate the carrying of mines, the after deck of the mine-laying destroyers had to be cleared and the torpedoes and aft gun removed. (Goss/Navpic)
Kaaveland reported the details of the incident in an updated radio signal to SDD3 at 05:30 and gave the co-ordinates he had received from the British officer, adding that the eastern side of Vestfjorden was closed to traffic. To pass the minefield, ships would have to leave undisputed Norwegian territory for several tens of nautical miles. From Tromsø, the signal was forwarded to Kommandørkaptein Askim in Narvik and to the Admiral Staff where it was registered at 05:58.68
While reading the signal, the duty officer at the Admiral Staff, Kaptein Håkon Willoch, was informed that the British and French naval attachés in Oslo were in the building, requesting an urgent meeting with him. Rear Admiral Hector Boyes and his French colleague Capitaine de Frégate d’Arzur wished Willoch a good morning and handed him a copy of a comprehensive memorandum, adding that at that very moment the original was being presented to the Foreign Office by their respective ministers, Dormer and de Dampierre. The memorandum, which Boyes insisted required ‘immediate attention’, argued at length how the deliberate increase in German violations of Norwegian neutrality and the Norwegian inability to prevent this, forced the Allied governments to take measures believed necessary. With reference to the memorandum of 5 April, of which Willoch had no knowledge, it had been decided to deny Germany the use of stretches of Norwegian territorial waters; three minefields had been laid that morning – off Stadtlandet, at Bud and in Vestfjorden. The co-ordinates of the minefields were given and it was added that British warships would patrol the fields for forty-eight hours to stop merchant ships entering the danger zones.69
At 05:10, Vevang coastguard station, near Hustadvika, reported two destroyers, ‘probably British’, having entered Norwegian territory, and the destroyer Sleipner was ordered out from Kristiansund to investigate. The two destroyers were indeed British. After departing with Renown in the morning of the 6th, Hyperion and Hero proceeded to Sullom Voe for refuelling. They left again at 05:15 on the 7th with orders to head for Bud on the Norwegian west coast and pretend to be laying a minefield. By 03:15 on the 8th, Ona Lighthouse was sighted and an accurate position obtained. The dummy mine-laying was commenced a little after 05:00. The two destroyers ran at slow speed side by side, heading back and forth on parallel tracks. When three fishing boats were sighted, oil-drums filled with seawater were dropped at the inshore end of the lines to give the impression they were laying mines. After about an hour thus pretending, the destroyers took positions, one at each end of the ‘minefield’, to warn off approaching vessels.
Around 07:20 Sleipner approached Hyperion with the signals ‘Protest’, ‘Violation’ and ‘Neutral waters’ hoisted. Hyperion returned ‘Minefield ahead. Stop for instructions’, followed by ‘Am sending boat’. A boat was lowered and Lieutenants Egan and Treseder came across, in spite of the adverse weather conditions. According to Egan, Kaptein Ullring received them ‘most courteously . . . and in perfect English . . . a charming man, who had been at sea for 35 years both in sail and steam’.70 Lieutenant Egan presented Ullring with a copy of the Admiralty’s signal giving the co-ordinates of all three alleged minefields off the Norwegian coast, adding that three hundred mines had been laid within the marked co-ordinates earlier that morning. The astonished Ullring repeatedly asked the British officers if the mines really had been laid and told them he now feared German reprisals out of all proportion. Having submitted a signal to the SDS in Trondheim, Ullring invited the British officers to join him for breakfast while he awaited instructions.71
Norwegian destroyer Sleipner. Four 735-ton Sleipner-class destroyers were in commission by the end of 1939. Capable of thirty-two knots, they were the fastest ships of the RNN, but were comparatively under-gunned, armed with only three 10-cm guns, one 40-mm Bofors L/60 and two torpedo tubes Asdic and a fair number of depth charges on the quarterdeck made the nimble destroyers potentially dangerous adversaries for submarines. (Marinemuseet)
It took several hours before the answer came, and during the extended breakfast the rapport between the Norwegian and British officers grew very friendly. Ullring suggested that Sleipner should take responsibility for guarding the minefield if Hyperion and Hero would leave Norwegian territorial waters. Lieutenant Egan – who knew there were no mines – answered that this was probably acceptable, and Kaptein Ullring asked to be taken onboard the British destroyer to make the final agreements with Commander Nicholson (and undoubtedly take a look at his ship). By now, the weather was deteriorating fast, though, and he eventually decided to stay where he was. The answer from the commanding admiral finally came via Trondheim after 10:30. It was short and not very helpful: ‘. . . Protest against violation of neutrality . . . ref paragraph 17 of neutrality procedures.’ The British officers left Sleipner, having received a formal protest. Through some further signalling, Ullring accepted responsibility for guarding the ‘minefield’, whereafter Hyperion and Hero departed Norwegian territory at 11:38.72
At Stad, no British naval vessels had been observed and several ships had crossed the area after the minefield was supposed to have been laid. Receiving the information from the Admiral Staff that there was a minefield here too, Tank-Nielsen sent the torpedo boat Snøgg and two auxiliaries to patrol the area.
The first German knowledge of the British mine-laying was a signal picked up at 07:35 from the British radio station at Cleethorpes, announcing the three danger areas. Politically, this development could not have been timed better, as it underlined perfectly the need for a German ‘rescue operation’ in Norway. The minefields would not affect the landing operations, but they might disturb the supply and tanker traffic to the bridgeheads. The SKL believed the British warning might very well be a bluff, but during a telephone conference with Admiral Saalwächter, it was agreed that no chances should be taken and the danger areas avoided, if necessary by going outside the Leads.73
Meanwhile, events progressed at sea.
Glowworm and Hipper
The slow Nordic dawn became visible onboard the German battleships around 04:45 GeT in
