Russia’s defense ministry said Monday it has deployed mobile coastal defense missile systems on a northern Kuril island, part of a strategically located chain of islands that stretch between Japan and the Russian Kamchatka Peninsula.

Japan lays claim to the Russian-held southern Kuril islands, which Tokyo calls the Northern Territories, a territorial row that dates to the end of World War II, when Soviet troops seized them from Japan.

The Russian Bastion systems, which have missiles with a flight range of up to 500 kilometers (310 miles), were deployed on the island of Paramushir, the Russian defense ministry said Monday.