North Korean leader Kim Jong Un is said to have punished leading military figures in his regime for what it has described as “impure behaviour”.

The dictator of the insular state has reportedly launched a major shakeup of the General Political Bureau (GPB), its main organisation for political indoctrination and propaganda.

According to analysts, Mr Kim is attempting a “brutal and efficient” bid to tighten his grip on power by removing high-ranking members of the military machine.

So Hwang Pyong, powerful director of GPB, and deputy Kim Won Hong now face an uncertain punishment for “impure” activities, according to South Korean politician Kim Byung-kee after a briefing with his country's intelligence service reported by CNN.

South Korean intelligence agency the National Intelligence Service (NIS) first reported the power shift in North Korea’s top military authority.

The GPB was responsible for making sure the armed forces were properly educated in the nation's totalitarian ideology.

Its leader, the now-accused Mr Hwang, was one of the most powerful people in the country beneath Mr Kim.

His sudden removal is thought to be a way of removing any threats to the power of the supreme leader.

Andrei Lankov, a professor at Kookmin University in Seoul, told CNN: "He's playing musical chairs with key positions.

"Kim Jong-un doesn't want anybody in the military to stay in charge for too long... He's brilliant, cynical, brutal and efficient."

According to South Korean news agency Yonhap, the GPB is about to be audited for the first time in 20 years.