The Battle of Iwo Jima was the American capture of the island of Iwo Jima from the Japanese during the Pacific Campaign of World War II. Ground fighting on the island lasted from the landings of February 19 to a final Japanese charge the morning of March 26, 1945. The U.S. invasion, known as Operation Detachment, was charged with the mission of capturing the airfields on Iwo Jima. On the night of March 25, a 300-man Japanese force launched a final counterattack in the vicinity of Airfield Number 2. Army pilots, Seabees and Marines of the 5th Pioneer Battalion and 28th Marines fought the Japanese force until morning but suffered heavy casualties—more than 100 were killed and another 200 Americans were wounded. The island was officially declared "secured" the following day.