The Siege of Port Arthur saw the introduction of much technology used in subsequent wars of the 20th century (particularly in World War I) including massive 11 in (280 mm) mortars capable of hurling 500-kg (1100-pound) shells over 8 km (5.0 miles), as well as rapid-firing light howitzers, Maxim machine guns, bolt-action magazine rifles, barbed wire entanglements, electric fences, arc lamp searchlights, tactical radio signalling (and, in response, the first military use of radio jamming), hand grenades, trench warfare, and the use of modified naval mines as land weapons.