Iraqi government forces gesture from their vehicles in the village of Mohammadi, a few miles north of Hit, in Iraq's western province of Anbar on Friday. (Moadh Al-Dulaimi/AFP/Getty Images)

A U.S. Marine was killed near the front line with the Islamic State in northern Iraq on Saturday, becoming the second combat casualty of the war against the militants, according to the U.S. military and Iraqi officials.

The Marine died when Islamic State militants fired rockets into a small U.S. base in Makhmour, a front-line town controlled by Kurdish peshmerga forces on the outskirts of the region of Kurdistan, U.S. officials said.

“Several” other Marines also were injured in the rocket attack, according to a Pentagon statement. An earlier statement had not specified which branch of the military had been involved.

A senior Iraqi army officer in Makhmour said two rockets landed about 8:20 a.m. Saturday on the U.S. camp, a small, closely guarded facility where American advisers have been based for several months helping Iraqi army and peshmerga forces battle Islamic State fighters nearby and preparing for an offensive to recapture the key Iraqi city of Mosul.

[Pentagon: Iraqi units move into Kurdistan in prep for battle of Mosul]





The death “reminds us of the risks our men and women in uniform face every day,” the Pentagon statement said.

“Our thoughts and prayers are with the service members involved, their families and their coalition teammates who will continue the fight against ISIL with resolve and determination,” it added, using an acronym to refer to the Islamic State.

U.S. officials did not specify the precise role of the Americans serving on the base. But elite Marine Raiders are deployed in Iraq with a mission similar to that of the Special Operations forces there.

The base lies within a larger peshmerga facility and next to an Iraqi army base on the outskirts of Makhmour, a town 30 miles south of Irbil, the Kurdish regional capital, which the Islamic State seized briefly in 2014.

Makhmour is expected to become a major focus of any offensive to retake Mosul, and Iraqi army reinforcements have begun arriving there in recent weeks in preparation. The Iraqi officer said that mortar and rocket fire frequently hit the Iraqi army base, making it unclear whether the attack that killed the Marine was targeting the Americans.

Brett McGurk, the U.S. special envoy to the coalition formed to fight the Islamic State, last week declined to predict when the offensive might take place, but he said it had effectively begun, with operations elsewhere aimed at severing supply routes and isolating the city. “It’s already started. . . . It’s a slow, steady squeeze,” he told a forum at the American University of Iraq at Sulaymaniyah.

He indicated that a full-scale offensive may take time. “It’s going to be a long campaign,” he said.

The first U.S. combat casualty in the 19-month-old campaign came in October, during a Special Operations raid to free prisoners of the Islamic State in the northern Iraqi town of Hawijah. The military identified the slain soldier as Master Sgt. Joshua L. Wheeler, 39, of Roland, Okla.

Salim reported from Baghdad. Dan Lamothe in Washington contributed to this report.

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