Islamic State militants, who once relied on wealthy Persian Gulf donors for money, have become a self-sustaining financial juggernaut, earning more than $3 million a day from oil smuggling, human trafficking, theft and extortion, according to U.S. intelligence officials and private experts.

ISIS fighters hold their weapons as they stand on confiscated cigarettes before setting them on fire in the city of Raqqa,April 2, 2014. REUTERS/Stringer
ISIS fighters hold their weapons as they stand on confiscated cigarettes before setting them on fire in the city of Raqqa,April 2, 2014. REUTERS/Stringer

The extremist group’s resources exceed that “of any other terrorist group in history,” said a U.S. intelligence official who, like others interviewed, spoke on condition of anonymity to discuss classified assessments. Such riches are one reason that American officials are so concerned about the group even while acknowledging they have no evidence it is plotting attacks against the United States.

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The Islamic State group has taken over large sections of Syria and Iraq, and controls as many as 11 oil fields in both countries, analysts say. It is selling oil and other goods through generations-old smuggling networks under the noses of some of the same governments it is fighting: Kurdish-controlled northern Iraq, Turkey and Jordan.

While U.S. intelligence does not assess that those governments are complicit in the smuggling, the Obama administration is pressing them do to more to crack down. The illicit oil is generally transported on tanker trucks, analysts said.

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