South Korea and the United States fired eight surface-to-surface missiles early on Monday off South Korea's east coast after North Korea launched a barrage of short-range ballistic missiles the day before, a South Korea defence ministry official said.

North Korea fired eight short-range ballistic missiles toward the sea off its east coast on Sunday, likely its largest single test, a day after South Korea and the United States wrapped up their first combined military exercises involving an American aircraft carrier in more than four years.