Japan said Tuesday that it had successfully shot down a ballistic missile over the Pacific as part of joint efforts with the United States to erect a shield against possible attacks from North Korea, the Associated Press reported. Japan tested the US-developed Standard Missile 3 (SM-3) interceptor from a warship in waters off Hawaii, becoming the first US ally to successfully intercept a target using the system. Defense Minister Shigeru Ishiba described the successful test as "extremely significant." "We will continue to strive to increase the system's credibility," he told reporters, insisting that the missile shield was worth the high cost. "We can't talk about how much money should be spent when human lives are at stake." The Japanese destroyer Kongou launched the missile from waters off Hawaii, which at 7:12 am Japan time (2212 GMT Monday) intercepted the target missile fired earlier from onshore, Japan's naval force said in a statement. "The Maritime Self-Defense Force will continue to cooperate with the United States and improve the capability" to shoot down incoming missiles, it added. The interception was made about 100 miles above the Pacific Ocean, officials said. The test was "a major milestone in the growing cooperation between Japan and the US," Japanese Rear Admiral Katsutoshi Kawano and Lieutenant General Henry Obering, director of the US Missile Defense Agency, said in a joint statement.