The U.S. Pentagon says its test of a missile shield designed by Boeing and Raytheon was successful. A U.S. interceptor missile on Friday (September 28) shot down a dummy warhead replicating an incoming North Korean missile in the seventh successful test of Boeing Co's long-range missile shield, the Pentagon said. The Missile Defense Agency said in a statement it completed a test "involving a successful intercept by a ground-based interceptor missile designed to protect the United States against a limited long-range ballistic missile attack." The interceptor missile was launched from an underground silo at Vandenberg Air Force Base on California's central coast, and its target was fired from Alaska's Kodiak Island. Raytheon Co said a radar it developed, which was located at Beale Air Force Base in California, tracked the target for about 15 minutes during its flight to the intercept point several hundred miles west of California. The 85 million U.S. dollars test was a rerun of one that was supposed to have taken place in May but was postponed when the target misfired. The test marked the sixth successful downing of a target in 10 full-fledged intercept tests since October 1999 in which knocking down the target was the primary objective, said Richard Lehner, a spokesman for the Missile Defense Agency. U.S. critics say the missile defense tests prove little because they are highly scripted. They say an attacker would use decoys that would likely foil U.S. defences.