US warns of friendly fire as Mosul's battlefield shrinks

An Iraqi Special Forces soldier takes position near the destroyed al-Hadba minaret as they fight Islamic State militants in the Old City of Mosul, Iraq, Friday, June 30, 2017. (AP Photo/Felipe Dana) (Copyright 2017 The Associated Press. All rights reserved.)

MOSUL, Iraq – U.S. Army Col. Pat Work and a small team of about a dozen soldiers drove through western Mosul in two unmarked armored vehicles. Iraq's Prime Minister had just declared the end of the Islamic State group's caliphate the day before, but the fighting still raging on as Iraqi forces prepared for another big push Saturday morning.

The American Colonel had a series of urgent calls to make: to talk face-to-face with generals from the Iraqi Army, the federal police and the Iraqi special forces. While the gains in the Old City are bringing Iraqi troops closer to victory against IS in Mosul, they also mean three branches of the country's security forces are now fighting in closer quarters than ever before. The new battle space and lingering communication shortcomings mean Iraqi ground troops are at increased risk of being hit by non-precision fires like mortars and artillery by their partner Iraqi forces, he explained.

Throughout the course of the day Work shuttled between bases and command centers inside the city meeting with Iraqi commanders deep inside Mosul, underscoring the increasingly prominent U.S. role in the offensive as it enters its final days.

A bomb explodes behind the al-Nuri mosque complex, as seen through a hole in the wall of a house, as Iraqi Special Forces move toward Islamic State militant positions in the Old City of Mosul, Iraq, Thursday, June 29, 2017. (AP Photo/Felipe Dana) (Copyright 2017 The Associated Press. All rights reserved.)

"It's a very violent close fight," said Work, the commander of the 82nd Airborne's 2nd Brigade Combat Team who deployed to Iraq in January. "When the bullets aren't enough the commanders want to turn to high explosives which might be mortars or artillery... so understanding where the other guy is all the time is kinda rule number one, so the lethal effect is directed at the target and not accidentally at another player that's on your team."

The various forces that make up Iraq's military have long struggled with coordination. While the Mosul operation is overseen by a joint operations command and the Prime Minister, forces on the ground maintain independent command structures, standards and cultures. The Mosul fight is the first time all three forces have had to cooperate in an urban environment and throughout the operation the army, federal police and special forces have faced deadly setbacks when they acted independently, allowing IS fighters to concentrate their defenses on a single front.

"We're helping (Iraqi forces) see across the boundaries between their different units... just helping them understand where they are and how rapidly things might be changing." said Work.

One of Work's stops was at a modest house in a residential west Mosul neighborhood. About a dozen U.S. troops and Iraqi soldiers were hunched over computers identifying IS targets just a few hundred meters away ahead of the next day's operation. The presence of U.S. forces at the small patrol base deep inside Mosul is a level of support that had not been authorized when the Mosul fight first began.

Under the administration of U.S. President Donald Trump, Defense Secretary Jim Mattis moved U.S. combat advisers closer to the fight by authorizing U.S. troops to partner with Iraqi forces at the battalion level.

The U.S.-led coalition's fight against IS in Iraq has slowly expanded over the past three years from a campaign of airstrikes carried out by coalition forces who largely stayed within heavily fortified bases to an operation with some 6,000 American troops on the ground, many operating close to frontline fighting. The evolution suggests that despite a large training program designed to generate enough soldiers to retake Mosul, Coalition officials assessed Iraqi forces lacked the tactical skills to conduct the operation without close support.

An Iraqi boy carries heavy belongings through rubble as he flees fighting between Iraqi special forces and Islamic State militants, in western Mosul, Iraq, Monday, May 15, 2017. (AP Photo/Maya Alleruzzo) (The Associated Press)

Between meetings, as Work's vehicle rolled through a traffic circle in western Mosul, he said being on the ground beside his Iraqi counterparts is essential.

"For any commander there is no substitute for seeing it with your own eyes... for talking to the stake holders who are in it making the decisions every day," he said. "ISIS has no boundaries, so our adviser network can't have any boundaries. And so part of it is getting out there daily to see it."

Work's one-on-one meetings inside Mosul come with a huge operational footprint. During his visit Friday a team of dozens of U.S. soldiers — most young men on their first deployment — provided him security and handled logistics. At each patrol base inside Mosul where U.S. troops work with Iraqi forces there can be dozens to over a hundred soldiers deployed to protect a team of just 10 advisers.

With the vast majority of Mosul retaken from IS, soldiers trained by the coalition to fight in combat are now transitioning to act as hold forces to help provide security. Even after the last pockets of the city are retaken, Work said he doesn't expect that will necessarily mean an end to the U.S. role in Mosul.

"Mosul is going to be a challenge, ISIS is going to continue to challenge the hold," using an alternative acronym for the Islamic State group. He said U.S. troops would continue to facilitate coordination and provide advice just as they did during the offensive.

"We will continue to help Iraqi commanders recognize that this is what you fought for."