Middle East Turmoil

How ISIS managed to acquire $2B in assets

This undated file image posted on a militant website on Jan. 4, 2014, which is consistent with other AP reporting, shows Shakir Waheib, a senior member of the al-Qaida breakaway group Islamic State of Iraq and the Levant (ISIL), left, next to a burning police vehicle in Iraq's Anbar Province.

The jihadist terror group Islamic State of Iraq and al-Sham has become a powerful military force, wreaking havoc throughout Iraq. But ISIS is more powerful than just its estimated 10,000 fighters and ever-expanding weapons cache: It is also believed to control $2 billion in total assets.

The Guardian reports that the group, whose actions in Iraq could derail the world economy, began its sizable cash reserves with the acquisition of oilfields in eastern Syria. From there, ISIS grew its treasury by smuggling antiquities and resources out of the embattled state. The Guardian said the details were discovered from a trove of flash drives acquired by Iraqi officials less than two days before ISIS conquered Mosul—Iraq's second largest city.

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Despite the vast riches detailed on the drives, the group's real windfall came after it took Mosul. After seizing its banks, weapons, and resources, ISIS's total assets reached a staggering sum.

"By the end of the week, we soon realized that we had to do some accounting for them," a senior intelligence official told The Guardian. "Before Mosul, their total cash and assets were $875 million. Afterwards, with the money they robbed from banks and the value of the military supplies they looted, they could add another $1.5 billion to that."

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The official went on to tell The Guardian that ISIS had acquired $36 million from one Syrian region alone by selling relics up to 8,000 years old.

—By CNBC staff