Tensions High after New Revelations About N. Korea's Nuke Capabilities

Tensions are high after a new report shows that North Korea is capable of setting off another nuclear device at any time.

A South Korean official says the communist country still has unused devices at its main atomic test site.

A South Korean military representative said in a statement that Pyongyang "will be completely destroyed by ballistic missiles and high explosive shells," if North Korea shows signs of launching a nuclear attack.

North Korea detonated its fifth and most powerful bomb just three days ago. The country's repeated nuclear tests are raising worries that it is developing deadly warheads.

"North Korea continues to present a growing threat to the region, to our allies, to ourselves, and we will do everything possible to defend against that growing threat," U.S. North Korea diplomat Sung Kim said in a statement.

President Barack Obama has said the United States will work to toughen sanctions on North Korea.

"In addition to sanctions in the Security Council, both the U.S. and Japan, together with South Korea, will be looking at any unilateral measures as well as bilateral measures as well as possible trilateral cooperation," Kim added.