NNine North Koreans who drifted into Japanese waters aboard a small wooden fishing boat on Sept. 13 arrived at Incheon International Airport from Fukuoka on Tuesday.

They are three men, three women and three children. One of the men claims to be a grandson of Paek Nam-un, a former chairman of the North's rubberstamp Supreme People's Assembly.

But Foreign Ministry spokesman Cho Byung-jae declined to divulge their identities due to concerns for their safety.

North Korean defectors arrive at Incheon International Airport from Japan on Tuesday.

According to the Asahi Shimbun, one of them was quoted by a Japanese government interrogator as saying he used to carry a mobile phone and talked with a relative, who had defected to China, in an area near the North Korea-China border.

The Japanese daily reported that one of the defectors had a regular income but decided to flee for the sake of his children's future, while others recalled listening to South Korean propaganda radio broadcasts beamed at the North at night and hearing about a group of defectors who had drifted to Aomori before they were handed over to South Korea in 2007.

On arrival at the airport on Tuesday, the nine were taken to a an interrogation center in Siheung, Gyeonggi Province, where they are being questioned by a team consisting of interrogators from the National Intelligence Service, police, and the military. Questioning to find out their identities, motives and escape routes can take two or three months.

They will then be taken to the government resettlement center Hanawon, where they will spend three months learning to integrate into South Korean society.