US tests missile defence system as North Korea concerns mount

The US has for the first time successfully tested its defence system against an intercontinental ballistic missile (ICBM), say officials.
A ground-based interceptor was launched at a California air base and shot down a mock ballistic missile, the Missile Defense Agency (MDA) said.
The Pentagon said the test was long-planned but it comes amid increased tensions with North Korea.Read More…http://www.bbc.com/news/world-us-canada-40101629