It is believed that the victims were abducted to teach Japanese language and culture at North Korean spy schools.[10][8] Older victims were also abducted for the purpose of obtaining their identities[11], but these abductees are believed to have been killed immediately. It is speculated that Japanese women were abducted to have them become wives to a group of North Korea-based Japanese terrorists after a 1970 Japan Airlines hijacking and that some may have been abducted because they happened to witness activities of North Korean agents in Japan, which may explain Yokota's abduction at such a young age.[5][12]