South Korea said Monday that the number of defectors from communist North Korea had passed 20,000, as their plight in the impoverished state deepened, dpa reported.
A 41-year-old woman and her two sons were the latest North Koreans to flee to the South via China, the Yonhap news agency quoted Unification Ministry officials as saying.
Tens of thousands of North Koreans are believed to hide in China.
Defections accelerated following a famine in the mid-1990s, that is believed to have killed 2 million people, but slowed down in the last year, as China, Pyongyang's main remaining ally, stepped up repatriation, Yonhap said.
According to activists, repatriated North Koreans face imprisonment, torture or even death.
South Korea's government provides resettlement training, citizenship, cash incentives and support to find jobs for North Koreans, but the defectors often face discrimination.
North and South Korea never signed a peace treaty after the 1950-53 Korean War.