South Korea simulates attack on North's nuke site after test

SEOUL, South Korea — Following U.S. warnings to North Korea of a "massive military response," South Korea fired missiles into the sea to simulate an attack on the North's main nuclear test site on Monday, a day after North Korea detonated its largest-ever nuclear test explosion.South Korea's Defense Ministry also said Monday that North Korea appeared to be planning a future missile launch, possibly of an ICBM, to show off its claimed ability to target the United States with nuclear weapons