Start heading towards the designated area (Zocalo plaza; #1). There are a lot of different routes leading to your destination. I would recommend that you stick close to the main road. Once you're closer to a small junction, leave the rest of the team behind. You will have to return here very shortly. Turn left and proceed to the plaza. Lean out carefully. You'll notice a lot of enemy soldiers in the vicinity (#2).
Try making a few steps forward. A small window should appear on your screen (#1). Listen to what the general has to say. This mission objective is going to be delayed. You will receive new orders very shortly.