South Korea says it has uncovered a plot to assassinate the most senior official ever to have defected from Communist North Korea.
Two North Koreans, said to have been posing as defectors themselves, have been arrested on suspicion of being on a mission to kill Hwang Jang-yop.
Hwang, 87, once a close confidant of North Korean leader Kim Jong-il, defected to the South in 1997.