President Lyndon B. Johnson decides to undertake the sustained bombing of North Vietnam that he and his advisers have been contemplating for a year. Called Operation Rolling Thunder, the bombing campaign was designed to interdict North Vietnamese transportation routes in the southern part of North Vietnam and slow infiltration of personnel and supplies into South Vietnam. The first Rolling Thunder mission took place on March 2, 1965, when 100 U.S. Air Force and Republic of Vietnam Air Force (VNAF) planes struck the Xom Bang ammunition dump 100 miles southeast of Hanoi. From 1965 to 1968, about 643,000 tons of bombs were dropped on North Vietnam, and a total of nearly 900 U.S. aircraft were lost during Operation Rolling Thunder. The operation continued, with occasional suspensions, until President Johnson, under increasing domestic political pressure, halted it on October 31, 1968.