Mouse-holing

Mouse-holing is a tactic used in urban warfare, in which soldiers create access to adjoining rooms or buildings by blasting or tunneling through a wall. This tactic is used to avoid open streets where advancing infantry, caught in enfilade, are easily targeted by machine-gun and sniper fire.

Mouse-holing began to appear in military tactical manuals in World War II. With mouse-holing, combatants are able to move around an urban battlefield under cover, without needing to expose themselves to enemy fire or observation. A typical passage is large enough for a single file of soldiers. Large, unrestricted holes can compromise the structural integrity of the building, and offer little cover from opposing forces.

During the Battle of Ortona, the Canadian Army (which gave the tactic its name) used it to great effect. Using weapons such as the PIAT or anti-tank guns to breach the walls of a building (as houses within Ortona shared adjoining walls), the soldiers would then throw in grenades and assault through the mouse holes, clearing the top floors and making their way down, where both adversaries struggled in repeated close-quarters combat. Mouse-holing was also used to pierce through walls into adjoining rooms, sometimes catching enemy troops by surprise.

Similar to underground tunnels used in rural battlefields, mouse-holes can also allow forces to infiltrate behind enemy lines, providing a significant tactical advantage. In some cases, a mouse-hole will be camouflaged with furniture, especially when they are created to aid a defending force or a clandestine operation. When used in defensive positions, mouse holes often join and combine with underground tunnels. This was used by the Red Army of the Soviet Union during the Battle of Stalingrad, where it allowed troops to consistently infiltrate areas to the German rear that were supposedly cleared. The ubiquitous availability of the Panzerfaust in the last months of the war made all sides use it to quickly breach buildings from unexpected directions.

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