Japan failed to intercept a ballistic missile target off Kaua'i today in a second test of the nation's ship-based Aegis ballistic missile defense system.

At 4:21 p.m., a ballistic missile target was launched from the Pacific Missile Range Facility. The Japanese destroyer JS Chokai detected and tracked the target using an advanced on-board radar, according to the U.S. Missile Defense Agency.

The Aegis Weapon System developed a fire-control solution, and at 4:24 p.m., a single Standard Missile-3 Block IA was launched.

Approximately two minutes later, the SM-3 failed to intercept the target. The Missile Defense Agency said there is no immediate explanation for the failed intercept.

More information will be available after a thorough investigation, the agency said. The JS Chokai crew performance was "excellent" in executing the mission, according to the Missile Defense Agency.

On Dec. 17 off Kaua'i, the Japanese destroyer Kongo shot down a ballistic missile target, marking the first time that an allied naval ship successfully intercepted a target with the sea-based Aegis weapons system.