This picture released by North Korea's official Korean Central News Agency in April 2017 shows howitzers during a military parade in Pyongyang.STR/AFP via Getty ImagesNorth Korea appears to have transferred different types of artillery systems to Russia.These are systems that have long threatened South Korea.The development comes as North Korean troops are fighting against Ukraine on behalf of Russia.North Korea appears to have sent its big guns to Russia, furthering its support of Moscow's grinding war against Ukraine, a conflict in which artillery has been a dominant player.The recent transfer of artillery pieces complements the thousands of troops North Korea has committed to the war to fight on behalf of the Russians and underscores the key role that shells and rockets continue to play in the conflict.Images began to surface on social media last week showing what were identified as North Korean "Koksan" 170mm self-propelled howitzers traveling by rail across Russia.The transfer of 170mm systems has since been confirmed by Western media reports citing South Korean intelligence, which says that Pyongyang has also transferred 240mm multiple rocket launch systems to Russia.Can Kasapoğlu, a non-resident senior fellow at the Hudson Institute think tank, said Wednesday that the 170mm and 240mm systems are the two most powerful that North Korea owns.The Koksan "has an operational range of 37 miles and can unleash an initial burst of four rounds in one minute, followed by one round every three minutes," Kasapoğlu wrote in a military situation report on Ukraine that was published Wednesday.North Korea now shipping artillery systems to Russia — this in addition to shells, men, and missiles it is already sending.