SEOUL, South Korea - North Korea (news - web sites) denied Sunday ever admitting to U.S. officials that it had a secret nuclear weapons program and said it would unleash a "sea of fire" if the United States challenges the communist country. AP Photo Reuters Slideshow: North Korea Nuclear Tensions Tension Mounts in Korean Peninsular (AP Video) The warning, issued over the North's state-run media and reported by South Korea (news - web sites)…showed first 75 words of 1046 total…

…showed last 75 words of 1046 total…the South Korean capital of Seoul, about 30,000 people rallied Saturday in support of the U.S. military presence as a deterrent to an attack from the North. But the tone in Pyongyang was vitriolic. Premier Hong Song Nam said North Korea was determined to "defend its right to exist from the U.S. imperialists who put an 'axis of evil' cap on us." Another official called for launching a "holy war" against the United States.