ISIS militants stand with a captured Iraqi Army Humvee at a checkpoint outside the Beiji refinery on June 19.
BAGHDAD - Iraqi security forces fought fierce battles with al Qaeda-linked militants Tuesday as both sides attempted to gain control of the country's largest oil refinery. Despite claims by Islamic State of Iraq and al-Sham (ISIS) militants that they had overrun the plant at Baiji, 120 miles north of Baghdad, a senior Iraqi security source told NBC News that the rebels had only taken some buildings. Government helicopters later attacked ISIS fighters near the refinery, the source added, speaking on condition of anonymity.
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The Associated Press reported Thursday that Sunni militants had hung their black banners on watch towers at the 300,000 barrel-per-day Baiji complex. Unease about the ISIS insurgency has led to fears about the oil supply being disrupted, sending gas prices spiking. In recent weeks ISIS has taken towns and cities across the country's Sunni-majority north and west, including its second city of Mosul. Secretary of State John Kerry was visiting the Kurdish city of Erbil on Tuesday to discuss the crisis with local leaders.