A weapon designed to blast nuclear missiles out of the sky has been tested at a Southern California coastal base, but failed to hit its target, Belfast Telegraph said.

The Missile Defence Agency said a ground-based interceptor missile was launched on Friday July 5. Its target was a missile launched 4,000 miles away from the Kwajalein Atoll in the Pacific Ocean.

But the interceptor did not hit its target. Officials will try to determine the cause of any anomalies that may have prevented a successful intercept.

The interceptor is one of about 30 deployed in Alaska and at Vandenberg Air Force Base under a missile defence programme begun in 2004.

In March, the Pentagon announced it would spend one billion dollars to place another 14 interceptors in Alaska.

The military said it would responding to North Korean progress on nuclear weapons.