In 1950, North Korea invaded South Korea, prompting the United Nations to authorize military intervention. President Harry S. Truman ordered US forces stationed in Japan to transfer to South Korea. Truman also sent US based troops, tanks, fighter and bomber aircraft, and a strong naval force to the area to support South Korea. As part of the naval mobilization, "Iowa" was reactivated on 14 July 1951, and formally recommissioned on 25 August, with Captain William R. Smedberg III, in command. "Iowa" sailed for Korean waters in March 1952. On 1 April she relieved her sister ship and became the flagship of Vice Admiral Robert P. Briscoe, Commander of the Seventh Fleet. In her first combat operation of the Korean War, "Iowa" fired her main guns near Wonsan–Sŏngjin on 8 April 1952, with the goal of striking North Korean supply lines. In the company of other naval vessels "Iowa" again engaged North Korean forces the following day, this time against enemy troop concentrations, supply areas, and suspected gun positions in and around Suwon Dan and Kojo. In support of South Korea's I Corps, "Iowa" shelled enemy positions on 13 April, killing 100 enemy soldiers, destroying six gun emplacements, and wrecking a division headquarters. The next day she entered Wonsan Harbor and shelled warehouses, observation posts and railroad marshaling yards before moving out to rejoin the UN flotilla aiding ground forces around Kosong. On 20 April, in her first combat action above the 38th parallel, "Iowa" shelled railroad lines at Tanchon, where four railroad tunnels were destroyed, before sailing to Chindong and Kosong for a two-day bombardment of North Korean positions.