A Navy ship intercepted a medium-range missile warhead above the earth's atmosphere off Hawaii in the latest test of the U.S. missile defense program, the military said Thursday.

The military had initially scheduled the test for Wednesday but postponed the drill after a small craft ventured into a zone that had been blocked off for the event.

The USS Shiloh detected a medium-range target after it was launched from the Pacific Missile Range Facility on Kauai, then fired a Standard Missile-3 interceptor.

The interceptor shot down the target warhead after it separated from its rocket booster, more than 100 miles above the Pacific Ocean and 250 miles northwest of Kauai, the Missile Defense Agency said in a statement.

The agency said the test had been scheduled for months and was not prompted by indications that North Korea was planning to test launch a long-range missile.

A similar test was conducted successfully in November of 2005, marking the first time a ship at sea shot down a multi-stage missile.