The Islamic State in Mosul has turned the process of creating devastating car bombs into one that has all the hallmarks of assembly line efficiency. Iraqi Army and counterterrorism units are encountering car bombs with frustrating regularity, so much so that they have developed tactics, techniques, and procedures more designed to mitigate the damage when one eventually rolls into their patrol, rather than to outright stop them.

The Los Angeles Times conducted an interview with Iraqi counterterrorism soldiers, who have encountered dozens of up-armored car bombs as the Battle for Mosul continues to rage. According to Iraqi Staff Lt. Col. Muntadhar Salem, “It’s the tactic they use the most.”

The use of the car bomb has been a hallmark for jihadi violence in Iraq and Syria for years. The prominence of the tactic led to the U.S. military’s ubiquitous phrase “VBIED,” or vehicle-borne improvised explosive device.

Vehicles laden with explosives have killed thousands of soldiers and civilians since the start of the Iraq War. But the precision afforded by the use of a live, thinking operator behind the wheel of a car bomb greatly increases their effectiveness as a weapon on the battlefield. The suicide car bombs have been so successful, the Islamic State has created entire suicide car bomb battalions dedicated to their use.

To further enhance the probability of getting the bomb to its intended target, the ingenious use of homemade armor has proliferated, leading to vehicle suicide bombs that are nearly bulletproof and unstoppable.

To mitigate the threat, the Iraqi Army has tried to use earth-movers to create berms that can physically restrict an advancing car bomb. But the sheer size and densely packed urban areas that characterize Mosul make this tactic ineffective at completely stopping these weapons.

While clearing certain neighborhoods in Mosul, the Iraqi Army has uncovered evidence of car bomb assembly lines, where each worker had a particular task in the process of outfitting a vehicle chassis with armor and storage capacity for the hundreds of pounds of explosives to be placed inside.