as "greif" made her way towards arendal, the torpedo boat encountered thick fog, forcing "kapitänleutnant" von lyncker to decrease the vessel's speed, delaying the arrival at arendal. according to the operational plans for the invasion, all the german landing groups were to arrive at their targets simultaneously at 04:15. "greif" arrived at arendal at 08:20. at 01:00, still more than seven hours from their objective, the germans had received radio reports of fighting taking place in the oslofjord. all the lighthouses along the southern norwegian coast, from marstein lighthouse in the west to the swedish border in the east had been turned off the previous evening, on the orders of commanding admiral henry diesen of the royal norwegian navy. although spotted by customs personnel as she made her way through the narrows leading to the town, the reports of the intruding warship did not reach lieutenant holthe on board "jo".