The island of Ie Shima lying 7 kilometres west of Motobu peninsula (The main stronghold) held one of the largest airfields in the Asia-Pacific region and was vitally needed to provide air support to the assault on Okinawa.
On April 16, aerial and naval artillery, rocket and mortar bombardment saturated Ie Shima to soften up the beachhead landing of the U.S infantry division. The area was defended by an estimated 7000 soldiers, many of whom were in hidden underground guard posts, caves and tunnels. Although the Japanese were encircled, they managed to hold off the American troops for 6 days using their heavy fortifications.
On April 21 Ie Shima was declared secure after 4,706 Japanese were killed and 149 captured with 1,500 Okinawan civilians dead. The success came at a cost of 172 Americans killed, 902 wounded and 46 missing (AWM 2005).