North Korea's state media released photos Thursday of what it said was the hull of a nuclear submarine. Its leader denounced South Korea's plans to build its own subs as "an offensive act."

North Korea said Wednesday its recent test-firings of sea-to-surface cruise missiles were successful, in another display of its growing military capabilities as U.S. President Donald Trump visits South Korea.

Experts say Kim likely hopes to restore ties with China, North Korea's biggest trading partner and aid provider, as there have been questions about the bilateral relationship.

When North Korean leader Kim Jong Un visits China next week for a military parade, it will be his debut at a gathering of foreign leaders for a rare meeting of China, Russia and North Korea.

With Russia's Vladimir Putin also coming for the parade, the event will underline the three-way alignment among Beijing, Moscow and Pyongyang in the face of a U.S. push to bolster its alliances with South Korea and Japan.

North Korean leader Kim Jong Un said he wants the luxury resort on the eastern seacoast to become a "world destination," but the country has been reluctant to allow in foreign tourists.

South Korean authorities plan to investigate the border crossing and did not immediately say whether they view the incident as a defection attempt.

The FBI announced Monday that four North Korean citizens have been indicted on wire fraud and money laundering conspiracy charges after allegedly scamming an Atlanta business.

North Korea sent 11,000 elite soldiers to support Russia. Their progress — especially in drone warfare — has implications not only for Russia's war on Ukraine but also peace on the Korean Peninsula.

The South resumed the daily loudspeaker broadcasts in June last year in retaliation for North Korea flying trash-laden balloons toward the South in a psychological warfare campaign.

The North Korean announcement came two days after Russia said its troops have fully reclaimed the Kursk region. Ukrainian officials denied the claim.

The recently signed mutual defense treaty could be used to justify thewidening of the war in Ukraine, as the U.S. says North Korean and Russian troops are already battling Ukrainian forces.

The U.S. says 8,000 North Korean soldiers are in Russia preparing to fight against Ukrainian troops in the coming days.

North Korea confirmed the launch hours after its neighbors detected the firing of what they suspected was a new weapon.

Russian President Vladimir Putin neither confirms nor denies the presence of North Korean troops in Ukraine. Putin’s comments came during a press conference at a Russian-hosted summit for the world’s top developing economies.