In World War I, some ships were refitted as armed merchantmen or auxiliary minelayers. These "minelaying cruisers" were the only purpose-built oceangoing minelayers of the Royal Navy. Another twelve ships were completed as destroyer minelayers. The ability of submarines to approach enemy harbours covertly led to their use as minelayers. In that time the United States produced twelve "Robert H. Smith"-class destroyer minelayers. These minelayers can carry several thousand mines and manoeuvre with high precision. She was then stationed in Immingham under the command of Senior Officer Minelayers. The US minelayers operating off Cape Moltke were also withdrawn. Other older units were used as dedicated minelayers. The two minelayers were acquired in 1941. In 1931, the KJRM acquired five former Austro-Hungarian minelayers, known as the . The Royal Navy lost 8 minelayers. Five locally-built "Malinska"-class minelayers were also added to the fleet in 1931. In November the "ouvrage" fired on German minelayers. The Lindormen class is a class of minelayers built for the Danish Navy.