South Korea repatriated a North Korean fishing boat that crossed the western maritime border due to an engine failure as three sailors aboard the ship wished to return to their homeland, the Joint Chiefs of Staff (JCS) said Friday. The Navy captured the North Korean boat that crossed the Northern Limit Line (NLL) in the Yellow Sea and sailed into South Korean-controlled waters Thursday evening despite repeated warnings to retreat to its territory. After the North Korean sailors told authorities that their ship drifted due to engine problems and they had no intention to defect, South Korea sent the ship back to the North at around 2:00 a.m., the JCS said. The intrusion took place in the eastern region near Baengnyeong Island, South Korea's northernmost territory in the Yellow Sea that lies off the coast of North Korea's Hwanghae Province. The Navy said it had held the North Korean ship in custody for the safety of the sailors considering the bad weather conditions. "Visibility was poor in waters east of Baengnyeong Island due to fog, and there were strong ebb currents at the time of the seizure," a JCS official said. A similar incident took place on Dec. 30. A North Korean fishing boat strayed into the South Korean waters due to engine problems before returning to its homeland. Drawn by the U.S.-led United Nations Command at the end of the 1950-53 Korean War, the NLL acts as the de facto sea border between the two Koreas. Pyongyang has said it does not recognize the line as legitimate, and the area has been the site of several bloody clashes between the two opposing sides.