A swathe of stories emerging from North Korea attribute the recent purge surrounding eminence grise Jang Song-taek to prosaic financial motives.

While some have suggested a trail of corruption in the military supply and other money-making business Jang had come to monopolize, others have traced the root cause to control of North Korean leader Kim Jong-un's overseas slush fund.

◆ Secret Bank Accounts

The regime is believed to have maintained a slush fund of an estimated US$4 million abroad since former leader Kim Jong-il. It is replenished to maintain the size whenever it is tapped into.

The only part of the slush fund that was ever definitely traced was an account in Banco Delta Asia in Macau containing $25 million that was frozen in 2005.

One diplomatic source in Seoul said, "The North Korean regime itself at the time was apparently glad to discover it, since they were unaware of the account."

The source added that almost all agencies have separate secret bank accounts overseas, so nobody has clear overview. If an official managing some of them is suddenly purged or dies, those accounts can be forgotten forever.

The U.S. and South Korea began tracing the secret bank accounts of the Kim dynasty following UN Security Council's sanctions against North Korea in 2006. More than 200 suspicious bank accounts surfaced in banks in Austria, China, Lichtenstein, Luxembourg, Russia, Singapore and Switzerland.

◆ Embezzlement Claims

Jang was responsible for managing North Korea's money-making business overseas as well as for economic reforms. One North Korean source said Jang and his cronies had been "deeply involved" in the North's secretive money-making operations since Kim Jong-il's rule, and it is likely that they continued to manage Kim Jong-un's slush fund as well.