(CNN)A U.S. Army Apache helicopter gunship for the first time in more than a year fired on an ISIS target in Iraq, a defense official told CNN.
U.S. uses Apache helicopter to hit ISIS
The Apache fired rockets Monday against a vehicle-borne IED south of Mosul -- signaling the first acceptance by the Iraqi government of the combat use of Apaches since the accelerated effort by the U.S. military against ISIS.
The Apache mission took place near the town of Qayyarah. U.S. airstrikes in the area support Iraqi, Kurdish and other militia units in their attempt to surround and isolate Mosul.
"I'm going to be careful about how far I go ... but they were employed against [an] ISIL target, an ISIL target was struck and the operation," Defense Secretary Ash Carter told reporters Monday.
"This is the first time that it's been called into action, and effectively," he added.
The official said they were last used in October 2014 to protect the Baghdad airport.
The U.S. had been pressing the Iraqi government for months to accept the offer to call in Apaches to help across Iraq in the fight against ISIS. The offer was rejected by the Iraqis in their campaign to retake Ramadi, but the U.S. official said the Iraqi government recently accepted the support.
Isolating Mosul and cutting off ISIS resupply lines in the immediate area is a top priority as the Iraqis try to make progress there, even as they are battling to defeat ISIS in Fallujah, which is located just west of Baghdad.
It had been thought the Iraqis might not move against Mosul for a few months, but the use of Fallujah as a haven to launch suicide attacks inside Baghdad has forced the Iraqis to deal with both areas simultaneously.
U.S. officials said there is no specific timetable to begin the assault on Mosul.
"I think its (the Apache) use was timely this time, or said differently, why the Iraqi and U.S. commanders decided to use it was because it -- it could be effective in helping those forces that are positioning themselves for the two-forked envelopment of Mosul," Carter said. "That's what it was used for, to help them along their way."
The Apaches are widely seen as very effective; they attack from a "standoff range" to minimize the threat of attacks against them from surface-to-air missiles.
In an interview with ABC News at the time the Apaches were used at the Baghdad airport, General Martin Dempsey, the then-chairman of the Joint Chiefs of Staff, said ISIS fighters were within 20 to 25 kilometers of the airfield, which led to the helicopter gunships being called in.
"Had they (ISIS fighters) overrun the Iraqi unit, it was a straight shot to the airport. So we're not going to allow that to happen. We need that airport," Dempsey told ABC.