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.

South Korea on Wednesday repatriated six North Koreans across the maritime border in the East Sea, months after they drifted into southern waters and were rescued.

Four sailors who had drifted over the disputed maritime boundary came in May. The other two entered southern waters in March and remained for four months, the longest known stay for any non-defectors