AMMAN, Jordan — Under the Islamic State group, Mosul has been transformed into an urban minefield littered with explosives and traps meant to bait troops and technicians into setting them off. Once Iraqi forces retake Mosul from the militants that have held it since 2014, they will have to contend with the city itself.

The US-led coalition and Iraqi military are hurtling toward a final assault on Mosul, which Iraqi Prime Minister Haider al-Abadi has said will occur by the end of the year. But NATO is concerned that, when the dust settles, the civilian population may return to an incredibly dangerous area saturated with improvised explosive devices (IED).

"If you look at Daesh's tactics, the way they defend towns is with 50 to 200 snipers and ten thousands of IEDs and booby traps," a NATO official said, using the Arabic alternative for the Islamic State group. "Everything is booby trapped. Children's toys, kitchen pots, the refrigerator, dead bodies, everything."

This month NATO began its second counter-IED course aimed at teaching Iraqi Army and Ministry of Interior officers how to disrupt explosive devices in an urban, humanitarian context. The treaty organization invited Defense News to Jordan to watch exercises and speak with some of the incoming students.

"In a street about 100 meters long, there will be more than 30 IEDS planted there," said one new student, a 29-year-old Ministry of Interior officer from Basra province who has been working as a counter-IED expert since 2012. The Iraqi officers interviewed for this article requested not to be named, citing danger to themselves and their families.

During the officer’s time working in Anbar, he helped disrupt 300 IEDs, including those in houses and vehicles, he said through a translator. Because he already came in as an expert, his focus will be working with instructors to enhance his skills and exchange information.

Most of the officers currently going through the program are less experienced, said Phil Yeaman, an instructor from ISSEE, a UK-based explosives training firm that contracted with NATO to teach Iraqi officers how to disrupt IEDs.

"I firmly believe — and I’m not criticizing them — but I firmly believe that the reason for the high level of casualties among their specialists [is] they have the principles … [but] the techniques are not what we’d expect from a trained specialist," Yeaman said.

"They are extremely conscientious. They are dedicated to the belief that they are defeating Daesh by improving the lot of their brothers, their co-mates, their fellow citizens," he added. "The skill sets of the Iraqis — they have the fundamentals, they have the principles. What we’ve tried to do is develop that into a more appropriate end result."

There are currently 30 Ministry of Interior and Army officers enrolled in the NATO program, two of which have already passed the course and are now assistant instructors honing their training skills. With ISSEE’s help, NATO hopes to produce 90 counter-IED operators by the end of the year, Yeaman said.

The IEDs used by ISIS are similar to those of other militant groups in the region, but their tactics are different and considerably more brutal. ISIS positions — and booby traps — explosives in such a way to bait counter-IED technicians into setting them off.

"Everything is on a bigger scale," Yeaman said. "Their area-denial systems are on [a] minefield scale. So we’re going to take weeks and months to clear the main field, bearing in mind the military would beach the minefield simply to have a safe path through it. The humanitarian aspect is to clear the area of all exploded remnants of war."

Counter-IED technicians work in a time-sensitive, non-permissive environment where they have to make decisions quickly, often under fire. Part of the challenge is teaching officers to slow down and take a more methodical approach. Another key aspect of the course is teaching Iraqi officers how to use everyday materials to clear IEDs so that they do not have to rely on any particular technology.

"There is a lot of high-tech equipment, and it’s all very good, it’s all excellent," Yeaman said. "However, if Iraq doesn’t have it, there’s no sense training them on it. If you take these guys and they’re out in a bush, there won’t be any resupply. They will have to revert to basics."

For that reason, trainees first learn how to make extremely simple, almost guerilla-style devices to defeat IEDs. During a live demonstration on Sept. 28., Yeaman taught officers how to use an empty plastic bottle filled with water and explosive liquid to make a "water bottle charge," which are then positioned next to IEDs and detonated. The resulting explosion destroys the IED’s circuitry without blowing up the device itself.

"The weakest point in any IED is the circuits, the wire," he said. "The mechanical connection, the solder to connect a piece of wire to a microswitch, these are weak points. So don’t worry about the main charge. Let’s attack the circuitry. Disrupt the circuitry, which makes it not go off, and then it’s quite simply a matter of recovering the explosive, disposing of it separately and recovering the switching for intelligence issues."

The trainees don’t study how to do the in-depth forensic analysis that help pinpoint the origin or maker of the IED, but part of their instruction includes learning how to properly package and store exploded materials for later investigation.

Once the trainees have learned how to use basic devices to disrupt IEDs, they learn how to use the more complex and reliable commercial solutions. But while Iraq has a lot of high-tech equipment, Iraqi officers are not able to count on resupply or proper sustainment of those capabilities, he said. For that reason, students return to homemade devices in the final phase of the program.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.