Islamic State fighters have captured seven oil fields in Iraq with a total output capacity of 80,000 barrels a day, adding to energy deposits they seized earlier in neighboring Syria, the International Energy Agency said.

The insurgents, who swept into northern Iraq in June, grabbed the Ain Zalah and Batma fields in Nineveh province this month, the IEA said today in its monthly oil market report. They already controlled the Najma, Qayara, Himreen, Ajeel and Balad fields, the agency said. The potential flow of oil from deposits they hold in Iraq would fetch about $8.4 million a day on international markets, based on yesterday’s closing price for benchmark Brent crude of $104.68 a barrel.

The militants, tapping oil fields to supply their own fuel needs and generate revenue by smuggling, have advanced toward Iraq’s self-governed Kurdish region and its capital Erbil, the IEA said. They were about 30 kilometers (19 miles) from the Bai Hassan field near Kirkuk, a northern oil hub and Iraq’s fourth-biggest field, it said. […]