SEOUL, South Korea (AP) – North Korea has added to its recent barrage of weapons demonstrations by launching four ballistic missiles into the sea while the United States sent two supersonic bombers over South Korea in a dueling display of military might. South Korea’s Joint Chiefs of Staff says the four short-range missiles fired Saturday flew about 80 miles toward the country’s western sea. North Korea has test-fired more than 30 missiles this week, including an intercontinental ballistic missile on Thursday that triggered evacuation alerts in northern Japan. It also flew large numbers of warplanes inside its territory in an angry reaction to a massive combined aerial exercise between the United States and South Korea. It included two B-1B bombers for the first time since 2017.