North Korea runs a cyber warfare unit that tries to hack into U.S. and South Korean military networks to gather confidential information and disrupt service, a news report said Tuesday.

North Korea took a fresh swipe at President Barack Obama on Monday, saying his administration is no different from that of his predecessor, George W. Bush.

A senior Obama administration official said he expects that North Korea will test a nuclear weapon before it is forced back to international disarmament negotiations.

A senior Obama administration official says he expects that North Korea will test a nuclear weapon before it is forced back to international disarmament negotiations.

North Korea said Friday it is intensifying its investigation into a South Korean worker detained on suspicion of denouncing the communist nation’s government, indicating it had no intention of releasing him any time soon.

Secretary of State Hillary Rodham Clinton says it is “implausible, if not impossible” that North Korea will return to international talks on ending its nuclear ambitions.

China has reopened its land border to tourists traveling to North Korea after a three-year break, with a group of 71 tourists visiting the isolated country, state media reported Thursday.

North Korea warned Wednesday it will fire an intercontinental ballistic missile _ or even carry out another nuclear test _ unless the U.N. apologizes for condemning the regime’s April 5 rocket launch.

North Korea threatened Wednesday to conduct nuclear and missile tests unless the U.N. apologizes for criticizing its April 5 rocket launch, dramatically raising its stake in the worsening standoff over its atomic programs.

North Korea has threatened to conduct nuclear and missile tests in anger over U.N. criticism of its rocket launch earlier this month.