North Korea on Wednesday demanded the return of two of its citizens found on a small wooden boat in South Korean waters, a day after nine other North Koreans spotted off Japan's coast were sent to the South for settlement.
More than 21,000 North Koreans have fled to South Korea since the end of the Korean War in 1953, with defections surging in recent years amid economic hardship in the North.
Defections are a sore point in relations between the divided Koreas; South Korea accepts those who choose to defect and repatriates those who wish to return home. But the North often claims that its citizens are held against their will in the South and that South Korean officials pressure them to defect.
On Wednesday, the North's Red Cross sent a message demanding that South Korea repatriate the two North Korean men found south of the eastern Korean sea border earlier this week, according to Seoul's Unification Ministry.
Officials were investigating whether the North Koreans intended to defect or had simply drifted south, and South Korea will honor their wishes, spokeswoman Park Soo-jin said.
In June, North Korea reacted angrily when South Korea refused to send back a group of nine North Koreans who crossed into South Korean waters by boat, citing their desire to defect. Earlier this year, Seoul allowed four of 31 North Koreans who had drifted south aboard a boat to remain in South Korea.
On Tuesday, nine North Koreans arrived in South Korea about three weeks after they were found on a wooden boat off the coast of Japan. Tokyo decided to honor their wishes to be sent to South Korea.
South Korean television footage showed the defectors wearing sunglasses, masks and hoods in an apparent attempt to conceal their identifies to protect the safety of their families left behind in the North. Those family members could be punished because of their relatives' defections.
North Korea has not officially commented on the nine defectors.
The two Koreas remain technically at war and their border is among the world's most fortified, meaning North Koreans seeking to flee often leave through the relatively porous frontier with China, some making their way to South Korea through Southeast Asia. Defection through Japan is rare.
Tens of thousands North Koreans are believed to be hiding in China, which is required to send them back under a treaty arrangement with Pyongyang. A South Korean civic group said that China arrested 35 North Korean defectors in border towns last month and is prepared to send them home, where severe punishment likely awaits.
South Korean officials were to visit China this week to try to verify the claim and stop any moves to repatriate the 35 defectors against their wishes, Seoul's Foreign Ministry said Wednesday.