A U.S. B-29 bomber dropped the world’s first atomic bomb over Hiroshima, Japan – an important military center with a civilian population close to 300,000.
South Korea's Defense Ministry says the B-52 bombers took part in aerial drills with other U.S. and South Korean fighter jets Friday over the peninsula.
Swedish think tank Stockholm International Peace Research Institute said that “we are drifting into one of the most dangerous periods in human history."