North Korea has appointed a senior communist party official as its new state security chief as part of leader Kim Jong-un's reign of terror aimed at preventing potential challenges to his power, a news report said Saturday.

Kim picked Jong Kyong-thaek, a member of the central military committee of the Workers' Party of Korea, to be the minister of state security, according to the Asahi Shimbun, a Japanese newspaper. It cited multiple sources with information on North Korea.

Kim Won-hong, a top officer in the North's military, was reportedly removed from the post earlier this year.

The replacement is in line with Kim's practice of blocking certain aides or organizations from building up too much authority, it added.

Last month, the Institute for National Security Strategy, which is affiliated with South Korea's National Intelligence Service (NIS), raised the possibility that Jong might have replaced Kim Won-hong.

Another Japanese newspaper, Tokyo Shimbun, reported that Kim has been sent to a collective farm in Pyongyang as a worker.

The NIS told lawmakers in Seoul earlier this week that the North is conducting an inspection of the General Political Bureau of the Korean People's Army.

Hwang Pyong-so, the bureau's chief, and Kim Won-hong, who also served as its deputy chief, were punished for "impure" acts, it added.

Choe Ryong-hae, the vice chairman of the party's central committee, has reportedly led the purge. (Yonhap)