South Korea fires missiles into the sea off its east coast during a live-fire drill meant as a warning to North Korea after the communist state conducted its sixth nuclear test.

South Korea fires missiles into the sea off its east coast during a live-fire drill meant as a warning to North Korea after the communist state conducted its sixth nuclear test. (South Korea’s Joint Chiefs of Staff)

SEOUL, South Korea — South Korea fired missiles in a mock attack on North Korea’s nuclear test site Monday, a show of force hours after Defense Secretary Jim Mattis warned that the United States would answer any threat from the communist state with a “massive military response.”

International condemnation mounted after North Korea conducted its sixth and most powerful nuclear test on Sunday at its mountainous Punggye-ri site.

President Donald Trump was asked by a reporter as he left church services on Sunday if he would attack the North. “We’ll see,” he responded.

South Korea’s defense ministry and other officials said Monday that the blast had a strength of 50 kilotons, which would make it about five times as powerful as the bomb that devastated Hiroshima during World War II.

Underscoring the threat, the Yonhap News Agency reported that South Korea’s spy agency expects the North to fire an intercontinental ballistic missile toward the northern Pacific Ocean. It didn’t give a timeframe or other details.

The North said it tested a hydrogen bomb that could be fitted onto an ICBM, although the exact nature of the blast had yet to be confirmed. It has demonstrated rapid progress toward its goal of developing a nuclear-tipped missile that could reach the U.S. mainland.

The communist state fired two ICBMs in July and sent a missile over Japan last month. Leader Kim Jong Un said the missile test over Japan was a “meaningful prelude” to a military plan to fire projectiles into the waters near the U.S. territory of Guam.

The escalation in North Korea’s testing activity and rhetoric has caused tensions to spike and raised fears that a full-fledged conflict could break out on the divided peninsula.

Trump has made bellicose statements in the past, including a threat to unleash “fire and fury” against the North. But his administration has stressed it’s focused on strengthening economic sanctions and diplomatic pressure that have so far failed to curb North Korea’s ambitions.

Mattis had tough words for the North after meeting with Trump and other national security officials.

He said the United States was prepared to defend its own territory as well as its allies South Korea and Japan from any attack.

“We have many military options, and the president wanted to be briefed on each one of them,” he told reporters in Washington.

“Any threat to the United States, or its territories – including Guam – or our allies will be met with a massive military response – a response both effective and overwhelming,” he added, calling on Kim to heed U.N. Security Council resolutions banning the North from using ballistic missile and nuclear technology.

“We are not looking to the total annihilation of a country – namely, North Korea,” he said. “But, as I said, we have many options to do so.”

The U.N. Security Council scheduled an emergency meeting for later Monday in what would be its second such session in under a week to discuss the growing threat from the North.

The U.S. maintains about 28,500 servicemembers in South Korea, which remains technically at war with the North after the 1950-53 conflict ended in an armistice instead of a peace treaty. @kimgamel

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