Finnish minelayer Louhi

Louhi was a Finnish Navy minelayer. The ship was originally constructed for the Imperial Russian Navy but was taken over by the Finns during the Russian Civil War. She had originally been named Voin, but was renamed as M1 in Finnish service. In 1936 she was given the more personal name Louhi, following the procedure of all other major ships in the Finnish navy.

The ship was designed as a minelayer but was not particularly good at it due to its slow speed, bad seakeeping qualities and inadequate storage space. During peacetime Louhi or M1 was used as depot ship with its storage rooms refitted as crew quarters.

Interwar period
From summer of 1919 M1 amongst other Finnish naval vessels was tasked with security and patrol duties the Koivisto region where the British naval detachment was located. On 12 September 1939 Louhi was moved to the Sea of Åland.

Winter War
Louhi laid mines to seaways at Kökar and Utö on the first night of the war. Louhi laid further mines on 3 December to seaway near Nyhamn but while laying the mines two of them exploded and the ship had to abort the laying of the mines midway. FINNISH GUNBOAT Uusimaa laid missing part of the mines on 4 December and the minefield was complemented by mines from Louhi on 5 December.

Louhi participated in laying of the minebarrier to the narrows near Märket by laying mines there on 9 and 14 December 1939. After Soviet submarines were seen to have penetrated the barrier Louhi on 10 January and auxiliary minelayer Baltic on 12 January laid more mines to the barrier which was strengthened with few kilometers of anti-submarine nets laid by auxiliary minelayer Frej.

Lapland War
On 12 January 1945 Louhi was returning from laying a minefield together with Ruotsinsalmi and was escorted by pair of MO-boats when a large explosion shocked Louhi. The vessel sank in two minutes taking 10 men with it while escorting Soviet ships saved the surviving crew from the freezing sea. The sinking was thought to have been caused by a mine but it was later revealed that the German submarine U-370 had launched two acoustic homing G7es torpedoes at passing enemy ships - one of these likely homed onto the Finnish minelayer, hitting and sinking her.