Begin the level heading West on the main road. Defeat the numerous soldiers in the area; some will be up the stairs near the building on the left, some will be hiding behind vehicles and debris. In the middle of the square behind the first destroyed vehicle will be two humvees with gunners, so be careful. Once the enemies are defeated, pass through the door where reinforcements kept coming from and go up the broken escalator. At the top, turn left and fight the soldiers in the room with the televisions. Beware, hostile reinforcements will come from the escalator behind you as you fight.
After the room is clear, pick up all three codes and continue up the staircase in the Southwest corner of the room. At the top of all the staircases, proceed West to the ladder and climb up. Once on the roof, beware the hostiles on the rooftops to the East and Northeast. Take the soldiers out then watch the staircase to the lower roof, as the helicopter will drop reinforcements nearby. Kill these soldiers and destroy the helicopters, then upload the codes.
