MCRP 12-10B.1, page 275

Using covered routes Moving after defensive fires have been suppressed or obscured Moving at night or during other periods of reduced visibility Selecting routes that will not mask friendly suppressive fires Crossing open areas (e.g., streets and spaces between buildings) quickly under the concealment of smoke and suppressive fires Moving on rooftops that are not covered by enemy direct fires. a. The requirement for speed may dictate movement through streets and alleys without clearing all buildings. When moving in this manner, the maneuver force should employ infantry to lead the column, and supported by AAVs, LAVs, wheeled vehicle-mounted machine guns, or tanks following. b. Marines should move along each side of a street with the leading squad staying abreast of armored vehicles. When not accompanied by armored vehicles, Marines move in a single file along one side of the street under cover of fires from supporting weapons. Individual Marines should be detailed to observe and cover a specific area, such as second-floor windows on the opposite side of the street. 5. Assault. Assault forces quickly and violently execute their assault and subsequent clearing operations. Momentum is maintained to prevent the enemy from organizing a more determined resistance on other floors or in other rooms. Small-unit leaders should keep the assault force moving without allowing the operation to become disorganized. a. An assault in a built-up area involves the elementary skills of close combat. Leaders must: Be trained in the required techniques to defeat the enemy in a face-to-face encounter Keep themselves in excellent physical condition Have confidence in their abilities and those of their unit. b. The composition of the assault force will vary depending on METT-T; however, its basic organization at the squad level consists of two assault elements carrying a fighting load of equipment and as much ammunition as possible, especially grenades. 6. Clearing. Entering at the top and fighting downward is the preferred method of clearing a building. Clearing a building is easier from an upper story because gravity and building construction become assets to the assault elements when throwing hand grenades and moving from floor to floor. However, this method is only feasible when access to an upper floor or Military Operations on Urbanized Terrain C - 3