QAYYARAH AIRFIELD, Iraq — Just a few months ago, the sprawling airfield at Qayyarah, south of Mosul, was a base for Islamic State militants.

Now, it’s home to hundreds of American troops as the U.S.-led coalition advises and assists Iraqi forces in their battle to retake the city, 40 miles away.

The U.S. military took me and other journalists on a tour of the base, also known as Q-West, on Tuesday.

Until the operation for Mosul began, forces here would sometimes come under mortar fire. The threat has diminished, but there’s still a threat, said Maj. Chris Parker, a spokesman for the U.S.-led coalition.

“It’s still a dangerous place, and a dangerous enemy,” he said. The U.S. military does not release exact numbers, but there are “less than 1,000,” coalition troops here, he said, as he drove through the base in the back of a hulking armored vehicle that is designed to be resistant to roadside bombs.

Ride in an MRAP - mine resistant ambush protected vehicles - built to withstand roadside bombs. #Iraq #qwest

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Islamic State militants tore down concrete blast walls and dug up and booby-trapped the runway here as they left, and the coalition has been helping to rebuild the base, which was also used by U.S. forces after the 2003 invasion. The airstrip is up and running again, with American C-130 planes ferrying in troops and supplies.

In addition to intelligence sharing and coordinating airstrikes, French and American troops here also give artillery support to advancing Iraqi forces, with the boom of the outgoing fire regularly echoing through the base, which has a perimeter of 15 miles. “Rocket city” reads the sign by several precision HIMARS rocket systems manned by U.S. troops.

They fire right into the city of Mosul from here.

HIMARS in action. #Qwest

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The Mosul operation is the Iraqi armed forces’ biggest endeavor since the U.S.-led invasion in 2003. “We are talking about liberating a massive urban area from multiple axis of advance,” Parker said. “That complicates the advise-and-assist mission.”

Since the operation was launched, the militants have battled hard to keep the fight out of the city, unleashing car bombs at Iraqi and Kurdish lines. They’ve also set fire to oil fields nearby and torched a sulfur plant, forcing coalition and Iraqi forces to wear gas masks when the wind blows the toxic fumes their way.

As Iraqi forces have moved closer to the city, resistance from the militants has been stronger, Parker said.

“I’m sure as they move into Mosul, it will be a tough fight.”

US soldiers at Q-West, where they are advising and assisting Iraqi forces pushing towards #Mosul

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