How did ISIL get so rich?

UPSOUND

They're not the kind of videos you're used to seeing from jihadist groups.

ISIL - the Islamic State in Iraq and the Levant - doesn't just have highly-produced recruitment films.

It's also considered to be the richest jihadi organisation in the world - even the Pentagon calls it "well resourced".

ISIL has captured territory in northwest and central Iraq with stunning speed.

That's partly due to its finances, says Firas Abi Ali from IHS.

SOUNDBITE: Firas Abi Ali, Senior Manager, MENA Country Risk IHS, saying (English):

"In a war, being able to fund yourself is a critical part of being able to survive. ISIL's funding definitely helps it establish itself and gain more territory, it helps it buy loyalities, it helps it pay various government workers to ensure that they show up, it helps it bribe other groups so that they pledge allegiance to it."

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It's not easy to find out exactly where ISIL get their money from.

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