At 4:30 a.m. on April 9, two torpedoes from Oscarsborg deliver the killing blow to the Blücher. She anchors near the Askholmene islets to try and get the fires and water intake under control. But by 5:30 a.m. the blaze reaches an ammunitions magazine. The resulting explosion rips an enormous hole in the bulkhead and the ship begins to sink.