N Korea 'execution' highlights Kim's insecurity

North Korea's Defence Minister Hyon Yong-chol has been executed, South Korea's spy agency has told parliament, apparently for not obeying instructions, and falling asleep at an event attended by Kim Jong-un.

Expert Michael Madden looks at what this tells us about the country's young leader.

Hyon Yong-chol's reported execution was a surprise to analysts but looking back at the history of the people who have held this position, he was probably not long for the post.

Four years, four defence ministers

There has been a high turnover of defence ministers

In four years, the position of defence minister has been held by four people. Mr Hyon is the only one to have been purged in such a brutal fashion - reportedly executed by anti-aircraft guns in front of an audience. Here's a rundown of the people to have held this position and their fates.

April 2012 - November 2012: Vice Marshal Kim Jong-gak held the position for just seven months. He is now the dean of a military university.

November 2012- April 2013: General Kim Kyok-sik is known to have passed away recently.

May 2013 to June 2014: General Jang Jong-nam occupied the post for just over a year and is still seen at military parades.

June 2014 to May 2015: General Hyon Yong-chol replaced him and has now reportedly been executed.

The context is that there have been multiple personnel shuffles in North Korea's senior military leadership. For example, the director of military operations, the post that controls all conventional military forces and links to special forces, has changed hands six times since Kim Jong-un's ascension.

Quiet military man with a lot of knowledge

There is little in Hyon Yong-chol's profile that tells us why Kim Jong-un may have wanted to eliminate him.

It was in 2010 that he was promoted to the rank of four-star general and on exactly the same day as Kim Jong-Un was promoted. That military promotion list was the North Korean leader's major public debut, a sign that he was the anointed one. His fellow general, Hyon, remained a relatively obscure figure.

But Mr Hyon is a man who would have had a lot of knowledge of North Korea's military situation. He supervised training schools and was the commander of the 8th army corps, stationed in the north-west near the border with China.

This is an area in which the Yongbyon nuclear research facility is located and where two missile launches have taken place. Mr Hyon will have had a detailed knowledge of this region. He was also in a senior position at some very critical points in the development of North Korea's arsenal: he had a lot of knowledge of weapons programmes and the army.

A demonstration of power and authority

This execution is likely to be entirely a demonstration of power and authority. This is indicative of Kim Jong-un's impulsive decision-making and a sign that he is not feeling secure.

It is unclear whether we are dealing with a personal issue of emotional security or basically the insecurity he feels in discharging the job of North Korean leader. There is the question of whether this is a clear and present danger to his ultimate authority or simply a power play. But ultimately, this is not the sign of a man confident in his job.

However with all these reshuffles, there is the persistent risk of instability.

And there are all kinds of interesting contexts to his reported death. First of all, it comes at about the time of the reported passing of former Defence Minister Gen Kim Kyok-sik, probably due to natural causes. So we are in a situation in North Korea where we have the death of two senior officials. One is being buried as a state hero and the other met his demise with ignominy.

But balancing power is not easy

Kim Jong-il also had to act as a balance between many entrenched interests

Like his father Kim Jong-un is in a balancing act between the many of entrenched interests in North Korea. Many of these are military interests and Kim Jong-un - whatever might be said about him - does know about military affairs. He is educated in the military and not just to a cosmetic degree. More than 50% of his time is spent doing military field inspections.

There are signs that North Korea is not getting much foreign direct investment and some people coming out of North Korea have indicated big problems with maintaining power supply.

Others may have fallen too

Hyon Yong-chol became chief of North Korea's military in 2012 after a political purge

But perhaps most interesting is the suggestion from some sources I have been in contact with - as yet unverified - that others may have been eliminated too. We know about the report from NK News about images - which could not be confirmed - showing large weaponry facing a very close target, a viewing area and several passenger vehicles.

They believe it could be a "gruesome public execution" by anti-aircraft fire, the way that Mr Hyon appears to have gone.