After the Ottoman Empire entered the First World War on 29 October 1914, the ships were involved in blockading the Turkish coast, participating in raids and minelaying operations. In early 1916, they helped to cover the Trebizond Offensive. In September 1916, they became part of a special detachment tasked with assisting the Romanian Army in Dobruja. was sunk on 30 June 1917 after hitting a mine laid by the Ottoman cruiser "Midilli" near Snake Island, with the loss of 44 men.