Region in focus: Faces in the fight for Mosul

Abdelyusef, no last name given, an Iraqi Federal Police officer, poses for a portrait at a checkpoint in the village of Al Kut.

Bergam Kadhim, from Najaf, Iraq, an Iraqi special forces soldier, poses for a portrait on a street in Gogjali, an eastern suburb of Mosul.

Abdelhakim Hamid, 19, from Qayara, Iraq, an Iraqi National Security armed guard, poses for a portrait in Qayara, some 50 kilometres south of Mosul.

A Kurdish Peshmerga soldier, no name given, poses for a portrait in Nawaran, some 20 kilometres north-east of Mosul.

Alaa Hashid, from Shura, Iraq, an Iraqi army soldier, poses for a portrait at a checkpoint in Qayara.

Hiwa Omar, 25, from Irbil, Iraq, a Kurdish Peshmerga soldier, poses for a portrait while guarding a checkpoint in Gwer, some 30 kilometres south-east of Mosul.

Haidar Hussein, 20, from Diwaniya, Iraq, an Iraqi army soldier, poses for a portrait while holding his machine gun on the outskirts of Qayara.

Raad Muqdam Al-Mosieh, 35, from Baghdad, Iraq, an Iraqi army soldier, poses for a portrait as he guards a checkpoint while wearing a gas mask on the outskirts of Qayara.

An Iraqi army soldier poses for a portrait in the village of Al-Hut, some 40 kilometres south of Mosul.

S Air Force Senior Airman Dennis Marshall, 26, from Memphis, Tennessee, poses for a portrait while holding his radio at the Qayara West Coalition base in Qayara.

Loay Mahdi, from Kirkuk, an Iraqi army soldier, poses for a portrait at the Qayara West Coalition base in Qayara.

The operation to drive ISIL out of Mosul has brought together an eclectic mix of Iraqis — young and old, police and soldiers, and a variety of irregular uniforms and equipment.

Often the forces look ragtag, sometimes professional. But many chose looks that are highly original for the fight, not expected to end anytime soon.

Not all soldiers wear uniforms, or markings, insignia or even body armour. One Iraqi army soldier wore only a T-shirt and a black-and-white scarf, proudly displaying his Soviet-designed PK machine gun. At a checkpoint in Gwer, 30 kilometres south-east of Mosul, a Kurdish peshmerga fighter wrapped his rifle in the colours of the Kurdish flag.

Iraqi police and intelligence have also joined the fray. One such recruit, just 19, wore a green medical mask while working as guard for national security forces.

A month into the offensive, dozens of troops and civilians have lost their lives, and thousands of residents have fled. Iraqi forces have a foothold in eastern Mosul and are advancing slowly, fighting house to house. But with IS fighting from within densely populated neighbourhoods, the battle for the city is far from over.

Here is a selection of portraits by AP photographer Marko Drobnjakovic of fighters taking part in the battle for Mosul.