Seoul, South Korea (CNN) Two key figures in the North Korean military have been punished for "impure behavior," according to a South Korean lawmaker, a move analysts say is likely intended to help leader Kim Jong Un tighten his grip on power.

A closed-door briefing by South Korea's National Intelligence Service (NIS) identified the two officials as Hwang Pyong So, the director of North Korea's General Political Bureau (GPB), and his deputy Kim Won Hong, said South Korean Rep. Kim Byung-kee after the meeting.

The General Political Bureau, which is also referred to as the General Political Department (GPD), is being audited for the first time in 20 years, Rep. Kim added, citing the NIS.

It's unclear how exactly how Hwang and his deputy were disciplined, but one analyst told CNN they could have been required to undergo re-education, which is likely to include a period of re-indoctrination of North Korean ideology.

"He's playing musical chairs with key positions," said Andrei Lankov, a professor at Kookmin University in Seoul and the director of NKNews.org . "Kim Jong Un doesn't want anybody in the military to stay in charge for too long ... He's brilliant, cynical, brutal and efficient."

Hwang Pyong So, left, stands near North Korean leader Kim Jong Un, second from right, during the opening ceremony of the Ryomyong residential area in April in Pyongyang, North Korea.

Before his punishment, Hwang was one of three officials below Kim Jong Un in charge of the armed forces. The other two are the defense minister and the chief of the general staff, according to Lankov.

"Their duties are sort of delineated, but they have a great deal of overlap. Altogether, they control the military," Lankov told CNN.

The General Political Bureau is in charge of making sure the armed forces were properly indoctrinated and educated in communist teachings, North Korea's state ideology of Juche, and the life and teachings of the Kim family, among other things.

GPB members can overrule higher-ranked military officials and its most senior members are granted body guards and special privileges, according to Michael Madden, an analyst who runs the Political commissars are assigned to various branches of the military to ensure it is ideologically sound.GPBmembers can overrule higher-ranked military officials and its most senior members are granted body guards and special privileges, according to Michael Madden, an analyst who runs the North Korea Leadership Watch project.

"It's one of the most powerful entities in North Korea," Madden told CNN.

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daring The high-level military shake-up comes just one week after thedaring defection of a North Korean soldier across the demilitarized zone.

The soldier fled his post on the North Korean side of the border and was shot five times as he dashed toward Freedom House on the South Korean side.

South Korea's Ministry of Defense confirmed to CNN more than 40 bullets were fired at the defector from pistols and an AK-47 during his escape. He is now in intensive care.

Hwang's department was in charge of making sure soldiers like the defector are properly indoctrinated and never contemplate fleeing. The unnamed soldier is the third to have defected from North Korea's military this year.

"Even if there had not been any issues with Kim Won Hong or Hwang Pyong So this year, they would've come down hard on the General Political Department," Madden said. "What they would say is this man that escaped from his guard post in North Korea is not ideologically sound."

The man who is now presiding over the GPB, according to Madden, is the same man South Korea's NIS says organized the punishment: Choe Ryong Hae, the vice-chairman of the ruling Workers' Party of Korea who himself used to run the GPB.

Choe was one of the officials who met with Chinese envoy Song Tao for rare talks between North Korea and China last week, according to state media from both countries.

Choe Ryong Hae, left, shakes hands with Song Tao, the head of the Chinese Communist Party's International Liaison Department, at the Mansudae Assembly Hall in Pyongyang Friday.

'If you are not lucky, you are just dead'

Kim Jong Il, the current leader's father and predecessor, was notorious for pitting his aides and underlings against each other to keep them afraid and on their toes.

Analysts differ to what extent Kim Jong Un uses the same practice. North Korea is sealed off from the rest of the world; getting information on everyday life outside of the capital of Pyongyang is hard enough. Understanding the inner workings of the highest echelon of North Korean leadership is even tougher.

But many North Korea watchers agree Kim constantly purges and replaces military leaders before they get too powerful.

Lankov says that since Kim took power in 2011, top military leaders are only averaging about a year in their jobs.

"If you look at generals, they are purged and replaced with unprecedented frequency," he said.

"Once you get some kind of power support base, you are out. If you're lucky, you are given some job as far away from the military as possible. If you are not lucky, you are just dead."

Kim's uncle, Jang Song Thaek, was a powerful general in his own right before the young leader came to power. Jang was believed to have a significant role in managing China's relationship with North Korea and had a hand in their lucrative cross-border trade relationship. Nearly 90% of North Korea's imports are from China, making it a vital lifeline for North Korea's economy and making Jang's role all the more powerful.

Jang would become an early victim of Kim's purges. He was declared "traitor for all ages" and executed in 2013, a move some analysts speculate was meant to send a signal to both China -- who hoped Jang would be a mentor to the younger Kim -- and North Korean generals who had accumulated wealth and power.

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This weeks' demotions can be traced back to that same logic, Madden says.

"What he doesn't want to have happen is what happened with his uncle, where you've got a bunch of very powerful guys and they start dominating the money and the control and they think they can disobey the supreme commander or not comply with his instructions," Madden said.

"The General Political Bureau has become very, very powerful under Kim Jong Un," he said. "They're being taken down a peg."

Hwang likely won't share Jang's fate, but will instead be sent for re-education for three to six months, Madden speculated.

"He was downgraded," Madden said. "He was basically the second name they used to introduce at North Korea's public events. He's now become number four."