North Korea said Wednesday it repatriated two South Koreans who allegedly sneaked into the communist nation last month during their trip to China, citing humanitarian grounds.

The Korean Central News Agency said that it sent a 59-year-old man, surnamed Lee, and a 51-year-old woman, surnamed Jin, back to the South earlier in the day via the truce village of Panmunjom, which sits on the inter-Korean border.

The KCNA said they should be handled by the North's law, but the North decided to send them back "from a humanitarian stand" as they admitted they "deliberately committed the crime and earnestly requested for forgiveness."

North Korea notified South Korea of its plan for the repatriation on Monday, saying that they "illegally" entered its borders last month. It is not immediately known why they entered the North.

The North has given a warning to the South that the repetition of similar "illegal" acts by South Koreans might entail serious consequences, according to the KCNA.

The Unification Ministry said that it took them into custody earlier in the day.

"The government plans to check their health conditions and investigate into why they entered the North," deputy spokeswoman Park Soo-jin said in a press briefing.

Seoul earlier said it had sought their whereabouts after learning they disappeared at the border with North Korea during their trip to China.

The North's move comes as Pyongyang said Monday it is ready to reopen talks with South Korea if certain conditions are met, including the suspension of Seoul's joint military drills with the United States. Seoul urged Pyongyang to come to the talks without any preconditions.

North Korea still is detaining four other South Koreans, including a missionary and a New York University student, spurning Seoul's request to set them free. (Yonhap)