North Korea is believed to have enough fissile material for at least 25 to 30 nuclear weapons.
North Korea called the U.S. "the kingpin of all kinds of terrorism who cannot even prevent terror in its own territory."
"I don't think Donald Trump can find North Korea on a map, frankly."
North Korea refuses to freeze its nuclear program.
Randy Schriver said he supported talking to the notoriously reclusive, militarized state in order to avoid a war breaking out.
The F-35B is a short-takeoff, vertical-landing aircraft.
North Korea said total "denuclearization is the aspiration and desire of humankind," but it needed nuclear weapons as long as it was threatened by the U.S.
China revealed it's building the world's fastest wind tunnel only a month after offering a glimpse of its new hypersonic DZ-ZF missile glider.
North Korea has backed communist insurgencies around the world, but never to the extent in which the U.S. was involved in global conflicts.
The four-day drills are set to conclude Tuesday.
South Korea said its military is maintaining combat readiness.
NATO "has intensified operative and combat training activities, including nuclear weapons use procedures," Russian Defense Minister Sergey Shoigu said.
The NATO chief said Kim Jong Un's potentially nuclear-capable missiles threaten Europe, but North Korea said it's the U.S. that's at risk.
Trump thinks Putin can help pressure North Korea.
Defectors claim that 80 percent of trees planted near the test site die, that underground wells have been evaporated and that babies in the region are born with birth defects at alarming rates.
Japan is the only country ever attacked with a nuclear weapon, and more than 72 years later it has the ability to build a bomb of its own.
A war with North Korea could lead to millions of deaths.
Americans are more fearful of North Korea in the Trump era.