Iraqi troops once again fled from a key battle for Mosul, the Islamic State’s headquarters in northern Iraq, as they began a long awaited offensive late last month to retake the city.

“The Iraqi Army commenced an assault on ISIS strongholds around Mosul, but when ISIS fired back, the Iraqi Army ran away and the assaults ended,” a western defense specialist based in Iraq told Fox News. “So now they are regrouping and rethinking their next options.”

When ISIS overran the city in June, 2014, Iraqi troops were criticized for dropping their advanced, American-financed weapons behind, and running away. ISIS is believed to be holding thousands of Christian, Yazidi and Kurdish captives and sex-slaves in the city with a population of more than one million.

After months of preparation, Iraqi troops began a highly anticipated offensive on the city last month and successfully retook a few outer villages that could be used to stage further attacks. But they quickly turned back to regroup in an obvious setback the army is casting as an unexpected need for reinforcements.

“These forces aren’t from that area necessarily, so they’re learning the area,” U.S. Army Maj. Jon-Paul Depreo told Fox News regarding the pause in the offensive.

Yakhi Hamza, the director of a volunteer aid organization that works with the Kurdish government in northern Iraq, told Fox News the fall-back is a signal the army still isn’t ready for battle, and ISIS will use the reprieve to fuel propaganda and its own troop morale.

“Nobody is optimistic about the ability of the otherwise well-equipped and trained Iraqi Army to retake the city,” he said. “Even if ISIS were pushed out of Mosul in the long run by the greater support from Peshmerga and [U.S.-led] Coalition, there is fear that they push the offensive towards Baghdad.”

About 4,500 Iraqi troops are geared up for the campaign to retake Mosul, along with a U.S.-led coalition of local militia and Kurdish forces.

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