(CNN) — Concerns grew Friday over the potential for U.S. forces to be drawn into ground combat against ISIS militants in Iraq after an attack on an air base housing U.S. military personnel.
A handful of militants attacked the strategic Ayn al-Assad Air Base, but were all killed before coming anywhere near the U.S. forces, the U.S. Central Command said in a statement.
“Well, it looks like they at least got to the outer base limits,” Pentagon spokesman Rear Adm. John Kirby told CNN. “We’re still looking at this and it’s hard to say whether they breached the perimeter or not. But they certainly got to the perimeter level at the very least.”
He said 20-25 people led by suicide bombers made the attack. Most, if not all, of the attackers were wearing Iraqi military uniforms, Kirby said.
The base is huge — roughly the size of Boulder, Colorado, Kirby said. That city is nearly 25 square miles. And U.S. forces were “several kilometers” away from where the fighting happened, the Pentagon said in a statement.
Ayn al-Assad, the largest military base in western Anbar province still under government control, is also where U.S. instructors train Iraqi pilots. Nearly 800 members of Iraqi security forces are training with coalition forces at the air base, the U.S. Central Command said.
And while military officials say the U.S. forces were not directly threatened in Friday’s skirmish, Kirby acknowledged that “no question that they’re close to danger.”
The U.S. team there — some 400 strong — doesn’t feel immediately threatened, but do have the “right, responsibility, obligation to shoot back” should militants threaten them, Kirby said.
U.S. officials have repeatedly downplayed the possibility of renewed ground combat in Iraq after the expensive and divisive U.S. combat operation that drew to a close with the final withdrawal of troops in 2011.
But U.S. and coalition airstrikes do continue in the area.
From Thursday into Friday, aircraft from the international coalition against ISIS carried out eight airstrikes in Syria and seven in Iraq, CENTCOM said.
Five of the Iraq airstrikes targeted ISIS units and equipment near Ayn al-Assad. The other two attacked targets near Mosul and Sinjar.
The Ayn al-Assad attack comes amid news that ISIS militants took full control of the western Iraqi town of al-Baghdadi early Friday, about 15 kilometers (9 miles) away from the Ayn al-Assad air base.
The ISIS fighters seized the city northwest of the capital of Baghdad, on Friday after attacking from three directions against Iraqi government forces, the security officials told CNN.
The squad that attacked the air base came in from the direction of al-Baghdadi, two security officals in the Anbar provincial office told CNN.
CNN’s Phil Black, said Friday that Kurdish Peshmerga fighters were starting to move from the north toward the city of Sinjar, held by ISIS since the summer.
The militants’ seizure of the city provoked a major humanitarian crisis as its ethnic minority Yazidi population fled onto the rocky slopes of Mount Sinjar, where many became trapped without food and water.
The Kurdish fighters are on the offensive but face a long, difficult battle to win back the city from ISIS, whose fighters are firmly in control there.
On Thursday, ISIS attacked Peshmerga fighters in Sinjar, as well as Kurdish forces positioned north of Iraq’s second-largest city, Mosul, and the town of Ba’shiqa, east of Mosul.
As fighting on the ground continued, ISIS pressed forward with its propaganda campaign.
The organization released photos purporting to show ISIS attacks on security checkpoints near Ramadi and posted video purporting to show them parading captured Peshmerga fighters through the streets in cages. ISIS claims the video was shot in the Kirkuk province of Iraq.
ISIS also offered up video showing them fixing roads in the al Nibai area, about 70 kilometers (43 miles) north of Baghdad.
CNN cannot confirm the authenticity of the images.