U.S.-led coalition aircraft destroyed an estimated $11 million worth of oil and trucks. It is the largest single airstrike this year against the Islamic State’s black market oil trade in Syria.

Coalition forces continue to hit petroleum and oil targets in Syria in an effort to disrupt the Islamic State’s cash flow. An estimated 83 oil tankers were destroyed in the effort. Sunday’s attack, led by A-10 Warthogs and F-16’s, shows that ISIL made a mistake by having such a large convoy in the open. The US feels it is making a dent in ISIL’s black oil trade.

“You’re going to have multiple effects from this one strike,” Air Force Lt. Gen, Jeffrey Harrigian, commander in the Middle East, said Tuesday. “We’ll have to see what this does to their ability to generate fighters.”

The attacks occurred in the Deir ez-Zor province, a key oil-producing region in Syria.

Taking away the Islamic State’s ability to generate revenue from selling black market oil has long been a tactic of US and coalition forces. The bombing campaign began two years ago and has resulted in the destruction of over 600 tanker trucks and other infrastructure. Being able to Hit 83 trucks in one attack is a telling mistake for ISIL.

“This is a very good indication that they’re having trouble commanding and controlling their forces,” Harrigian told USA TODAY in a telephone interview from his headquarters in Qatar.

With more than $1 million generated in oil revenue per day at its peak, the Islamic State had money to buy  equipment and weaponry, pay current fighters in the force, and recruit additional fighters to the effort. The US and its coalition partners hope to quell any possibility of ISIL expansion plans by cutting off funding through the destruction of “black” oil.

However, coalition pilots do fire warning shots at the oil convoys to signal an attack is imminent.

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“We’ll do that … to give them a chance to run,” Harrigian said.

You can read Jim Michaels full story here.