An Iraqi soldier keeps warm in front of a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. The mural behind him depicts the Islamic State group's dream of the conquest of Rome. (Seth Robson/Stars and Stripes)

An Iraqi soldier keeps warm in front of a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. The mural behind him depicts the Islamic State group's dream of the conquest of Rome. (Seth Robson/Stars and Stripes)

Damage done by the Islamic State group to a palace overlooking the Tigris River in Mosul, Iraq. (Seth Robson/Stars and Stripes)

Saddam Hussein's face was erased by Islamic State militants at a palace overlooking the Tigris River in Mosul, Iraq. (Seth Robson/Stars and Stripes)

A soldier pulls improvised explosive devices out of a hole beside a palace overlooking the Tigris River in Mosul, Iraq, on Wednesday, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

The Islamic State group eradicated the faces from this frieze on a palace in Mosul, Iraq, that once served as the headquarters for Gen. David Petraeus. (Seth Robson/Stars and Stripes)

The Islamic State flag is drawn inside a palace overlooking the Tigris River in Mosul, Iraq, that once served as Gen. David Petraeus' headquarters. ()

An Iraqi soldier stands guard at a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017 (Seth Robson/Stars and Stripes)

An Iraqi soldier climbs through rubble from an airstrike inside a palace in Mosul, on Wednesday, Jan. 25, 2017 (Seth Robson/Stars and Stripes)

A machine gun points toward the Tigris River from a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

View of the Tigris River from a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

This photograph shows the damage done by the Islamic State group to a palace overlooking the Tigris River in Mosul, Iraq. (Seth Robson/Stars and Stripes)

Iraqi soldires are wary of going too close to some of the palaces they have captured in Mosul, Iraq. The buildings are full of tunnels and may be booby-trapped. (Seth Robson/Stars and Stripes)

An Iraqi soldier sits in a palace window in Mosul on Wednesday, Jan. 25, 2017. The Islamic State mural behind him depicts the group's dream of the conquest of Rome. (Seth Robson/Stars and Stripes)

Iraqi troops stay warm in front of a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

Iraqi troops eat lunch behind a palace in Mosul, Iraq, on Wednesday, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

An Iraqi soldier stands guard at a palace in Mosul, Iraq, on Wednesdsay, Jan. 25, 2017. (Seth Robson/Stars and Stripes)

Iraqi special forces Capt. Aysar Ahmed Hassan, 36, poses in front of the wreck of a palace that was once U.S. Gen. David Petraeus' headquarters in Mosul, Iraq, on Friday, Jan. 27, 2017. On Independence Day, 2003, then Maj. Gen. David H. Petraeus, commander, 101st Airborne Division (Air Assault), administered the oath of reenlistment to more than 160 Screaming Eagle soldiers in front of the palace. (Seth Robson/Stars and Stripes)

Iraqi troops were holding positions on Friday, on Friday, Jan. 27, 2017, in a palace complex that was once an American base in Mosul. (Seth Robson/Stars and Stripes)

MOSUL, Iraq — Iraqi troops battled snipers, car bombs, mortars and anti-tank weapons to capture the palace complex that once served as the headquarters for Gen. David Petraeus in Iraq’s second-largest city. They are still wary of entering some of the buildings because of booby traps that have yet to be cleared by explosives experts.

The palaces, built by the late Iraqi dictator Saddam Hussein, were occupied by Petraeus, then a major general, and the soldiers he commanded from the 101st Airborne Division after the United States invaded Iraq in 2003.

Lt. Anwar al-Abad said he and his men killed 20 enemy fighters gaining entry to the complex during a battle on Jan. 20. Two days later, they killed another fighter who suddenly emerged from a tunnel under one of the buildings, he said.

Airstrikes have done massive damage to some of the palaces, but Iraqi troops have built a ramp out of the rubble to get to upper floors of one building. From there they’ve installed a heavy machine gun aimed at the Tigris river, which divides them from the western, enemy-held part of the city of 2 million people.

U.S., British and French special forces have been advising the Iraqi army units, and they have played a prominent role in calling in airstrikes against Islamic State targets inside the city.

During the U.S. occupation, the complex was surrounded by concrete walls and housed offices and a command center filled with maps and video screens, where commanders oversaw efforts to secure northern Iraq.

Petraeus drew on his experience there to revamp the Army’s counterinsurgency doctrine, then applied the lessons he learned to quell Iraq’s insurgency after assuming overall command in 2007. In the years since, the doctrine of securing civilian populations and winning hearts and minds has dominated U.S. military operations in Iraq and Afghanistan, where Petraeus also commanded.

On Friday, Iraqi commandos had firm control of the palace complex although mortar shells were still falling around them.

The radical Islamist militants, whose religion forbids images of humans and animals, defaced elaborate facades on the palaces that depicted Hussein, eagles and historical figures. In their place, they drew their black and white flag and created a large mural showing a hooded terrorist holding a knife in front of the Colosseum in Rome.

Capt. Aysar Ahmed Hassan, who commanded the unit in the palace, said he attended the U.S. Army Ranger School at Fort Benning, Ga., in 2010. The former high school chemistry teacher from Basra reminisced about tough training alongside U.S. and international Ranger candidates.

“The toughest part was the mountains,” he said of his time in America.

Having fought the Islamic State group in Ramadi and Fallujah before Mosul, he said he was eager to finish them off on the other side of the river.

“They call themselves Muslims, but they are out of Islam,” he said. “There is no killing people and taking people away from their houses in our religion.”

Hassan pointed out a brick with Arabic writing on it that someone had placed on a ledge overlooking the river. He translated the writing: “Saddam Hussein.”

“A lot of the people from the Baath Party are part of the Islamic State,” he said, referring to the Sunni-dominated political group that Hussein once led.

The damaged palace where Hassan and his men were camped looks as though it will need to be demolished, something that saddens the young officer.

“These palaces are like national treasures for the Iraqi people,” he said. “They shouldn’t have been destroyed,” he said.

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