U.S. Defense Secretary Jim Mattis is responding to North Korea's latest nuclear test by saying threats to the United States and its allies "will be met with a massive military response."
Mattis spoke at the White House on Sunday following a meeting with President Donald Trump and national security advisers. He says any response will be "both effective and overwhelming."
Mattis says the United States is "not looking to the total annihilation" of North Korea, but added "we have many options to do so."
North Korea claimed "perfect success" in an underground test of what it called a hydrogen bomb -- potentially vastly more destructive than an atomic bomb. It was the North's sixth nuclear test since 2006, but the first since Trump took office in January.