U.S. special operations forces reportedly have carried out several covert combat missions against ISIS over the past year, contrary to the Pentagon's insistence that operations like last week's raid of an ISIS-held prison in northern Iraq was a "unique" circumstance.

Bloomberg View reported that a special operations task force staffs an operations center in the northern Iraqi city of Irbil to support such missions. The report, which cited U.S. and Kurdish officials, claimed that the task force has worked in recent months to identify and locate senior leaders of ISIS. Members of the group also participated in last week's raid, during which Army Master Sgt. Joshua L. Wheeler was killed. Wheeler became the first American to die in combat since the launch of anti-ISIS operations last year.

At a Pentagon briefing in Baghdad Tuesday, spokesman Col. Steve Warren answered a question about whether U.S. forces in Iraq were in combat against ISIS in no uncertain terms.

"We're in combat," Warren said. "I thought I made that pretty clear ... That is why we all carry guns. That's why we all get combat patches when we leave here, that's why we all receive [an] immediate danger badge. So, of course we're in combat."

Last week, Cook said the raid on the ISIS prison in the town of Hawija was "consistent with our counter-ISIL effort to train, advise and assist Iraqi forces", using a different acronym for the terror group. He also said the rescue was a "unique" circumstance, but declined to say that it was the only time U.S. forces have engaged in a form of ground combat in Iraq. Instead, he noted that U.S. troops are "allowed to defend themselves, and also defend partner forces, and to protect against the loss of innocent life."

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Cook's previous comments had kept with a general avoidance on the part of administration officials to admit that U.S. troops were in combat. However, on Friday, Defense Secretary Ash Carter said while discussing the raid, "This is combat, things are complicated."

In addition to the death of Master Sgt. Wheeler, The Daily Beast reported earlier this week that five service members had been wounded in action since the start of operations in Iraq last year. However, the Pentagon has refused to disclose how and when they were injured. The Washington Post reported in March that one of the wounded service members was hit in the face by bullet fragments while coming under enemy fire. 

Bloomberg View reported that in addition to the special operations task force, the operations center also contains so-called Joint Terminal Attack Controllers, who work with U.S. allies and the Iraqis to coordinate combat flights against ISIS over Iraq. A third group, from the Marine Special Operations Command, is in charge of training Kurdish counter-terrorism forces.

On Tuesday, Carter testified on Capitol Hill that that the military plans a "higher and heavier rate of strikes" against ISIS targets. Separately, a senior U.S. official confirmed to Fox News that President Obama is considering proposals to move U.S. troops closer to the front lines in the fight.

On Wednesday, retired Gen. John Allen told the Senate Foreign Relations Committee that as the U.S. continues to build up its military options in Syrian, European nations might consider combat operations to battle extremists.

Allen said the U.S. military recently began asking its European allies to join it at Incirlik Air Base in Turkey where the U.S. is being allowed to launch fighter aircraft and surveillance missions in Syria.

"I expect that as time goes on, and as more opportunity becomes available to us, we may well see our European partners become more kinetically involved in Syria," Allen said.

"There may be opportunities in the south as well as in the north where our European coalition partners could in fact play an important role, and I'm thinking special operations," Allen said, adding that additional details could only be provided in a classified setting.

Fox News' Jennifer Griffin and the Associated Press contributed to this report.

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