Once you start the level run up the stairs and across the catwalk, kill the guy on the MG and look high his location. You will see the target inside the destroyed building.
Continue down to the MG and look on the side of the building just under the catwalk you crossed. You will find the poster tucked away next to a fence on the right hand side.
Continue forward until you need to life the garage door. Once you enter this next area look directly to your right as you enter and up. The target is on the ceiling in the corner.
Cross over this large area from Target 2 and look on the back of the concrete pillars on the left hand side. The poster is on the furthest pillar, closest to the fence.
Once you have cleared the area head through the broken garage door. After an in-game cut-scene you will come to a shutter you need to lift. Enter the mall and pay attention to the right side of the area. You will see several guys rush out of a door, and one will break through a window. Just to the right of the door you will find the next poster.
Once you pick up Poster 3 step to your right and look up at the balcony's above. The target is located within a sign high up on the 6th floor.
Head through the general store and out into the backroom. Once you see the payphone turn around and look on the right side of the doorway you just entered.
Head towards the payphone in the same room as Poster 4 and look up high at the balcony's above. You will need to be as close to the phone as possible to see this one.
As you head up the stairs from the phone you will enter a large balcony with a door you can lift on the left hand side. Lift the door and look directly to your left as you enter to find the poster on the wall.
From Poster 5 walk forward and past the door. Turn to your right, then look back towards the small dining area, you should see a broken roof tile in the center with the target hidden on top of it.