In fighting the Chechen rebels, the Russian army tried to take Grozny multiple times. Eventually they learned the basics of urban combat the hard way. Grozny 2000: Urban Combat Lessons Learned discusses some of these lessons — and some of the Chechens’ tactics:
The Chechens boarded up all first-story windows and doors, making it impossible to simply walk into a building. While trying to climb ladders or knock in doorways, Russian soldiers became targets for Chechen snipers positioned on upper floors. Reportedly the Chechens were divided into 25-man groups that were subdivided into three smaller groups of eight each that tried to stay close to the Russian force (again, ‘hugging’ the Russian force as during the 1995 battle to minimize the Russian artillery effort).The Chechen force had two months to prepare the city and they constructed a number of ambush points. The rebels had two defense lines, with the least-skilled personnel in the front. Snipers occupied roofs and upper floors of buildings, controlling distant approaches to specific intersections. They attempted to draw the Russians out into the street, according to the Chief of Grozny’s defense force, General Aslanbek Ismailov. Snipers also could be found in trenches and under concrete slabs that covered basements. These slabs could be raised with car jacks when Russian forces approached, provide ambush firing positions, and then drop back down. The attacking Russian force struggled to discern what was merely rubble and what was a kill zone.
The Chechens spent an inordinate amount of time digging trenches and antitank ditches for the city’s defense. Journalists reported that many men and women were taken from basements to dig the trenches. The Chechens used the trenches to move between houses and as sniper positions. As the Russian force focused on the tops of buildings or on windows, they were often attacked from the trenches, a sort of attack by misdirection. The Chechens stated that in the city they did not use body armor because it slowed them down, or tracers, which revealed their positions too precisely.
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Finally, the impressive mobility of the Chechen force included escape routes from firing positions, interconnected firing positions and again the sewer network to move about the city. Reportedly a computer in Grozny kept track of everyone in the city and other areas of Chechnya who reported in by radio. Russian forces especially feared the nighttime, when the Chechens would move against and reclaim abandoned positions. The Chechen force allegedly used chlorine and ammonia bombs, set oil wells on fire to obscure fields of vision and rigged entire building complexes with explosives. Other reports indicated that the Russians offered the Chechens safe passage out of the city and amnesty for those who could prove they were not involved in the fight.