The fishermen’s boats had drifted into South Korean waters, officials said. The South’s new president has been trying to improve ties with North Korea.

Top South Korean, U.S. and Japanese military officers are urging North Korea to cease all unlawful activities that threaten regional security, as the three nations fly advanced warplanes for a joint exercise in a show of force against the North.

Washington has said the treatment of Glavprodukt, the only U.S. company Moscow has seized, will influence a planned reset of U.S.-Russia relations.

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.

North Korea will not abandon its nuclear weapons. This is not a matter of opinion, but a strategic fact rooted in decades of historical precedent, failed diplomacy and shifting global dynamics.

South Korea sent six North Koreans back across their sea border, months after they drifted south in wooden boats in March and May.

The equipment activist Lee Min-bok uses to send balloons laden with anti-Kim Jong Un leaflets across the border from South Korea unto the North has been gathering dust and cobwebs for months. When it became clear that centre-left politician Lee Jae Myung was on track to win the June presidential election,

A North Korean man crossed the DMZ on foot before midnight Thursday, asking South Korean troops for help in a rare defection through the fortified border.