North Korean troops, who were working on construction and maintenance in the area, did not heed broadcasted messages to halt, an investigation said.

North Korea accuses South Korea of a “serious provocation” after South Korean troops fired warning shots Tuesday at North Korean soldiers setting up barriers along their tense border.

LONDON -- North Korean leader Kim Jong Un oversaw the test-firing of two newly developed types of missiles, state media reported, launches that came as the United States and South Korea held their annual military drills to the south.