Japan will conduct its first test-firing of a land-to-air missile interceptor in the United States in September to ensure that a missile shield for the Japanese capital will function properly if it falls under attack, the Defense Ministry said. The PAC-3 Patriot interceptor will be fired at White Sands Missile Range in the state of New Mexico during the week of Sept. 15, according to a ministry statement obtained Saturday. The test comes as Japan and the US accelerate their joint missile defense program following North Korea's missile and nuclear tests in 2006. The planned test "aims to confirm the functions of the Patriot system that has been upgraded with ballistic missile defense capabilities," the ministry said. Japan has been aggressively augmenting its missile defense capabilities amid concerns about a possible threat from North Korea. Japan plans to deploy the PAC-3 defense system at several more bases around the country by March 2011.