Allied forces increase drills to counter North Korean threat.

The US, South Korea, and Japan conducted a joint missile defense exercise in waters near the Korean Peninsula as they expand military training to counter the growing threats of North Korea's nuclear-capable missiles. The South Korea-U.S.-Japan training could trigger a belligerent response from North Korea, which condemns the United States' military drills with its Asian allies as invasion rehearsals. The United States and South Korea also launched drills Monday involving some 110 warplanes, including advanced F-35 fighter jets, that will continue through April 28.