After the departure from the Rat Patrol you will begin alone in some dark garage. Take all the items you find there and get outside through the debris. There is a way blocked by the stack of boxes. Approach it and press the triangle button to climb it.
Outside, the rebel's counterattack is going to be supported by the tank. Follow it carefully.
You can also follow the tank using the rooftops. When you get down stay away from the steel box, which can be destroyed any moment.
A few steps away you should spot a high building [A]. Go to the street near it, us the ladder and get to the rooftop. There you can eliminate the enemy sniper.
Search the rooftop - there is a Javelin missiles launcher. Get to the street level and move along. When all of the mercenaries are eliminated, just before the wire entaglements, you should find another ladder [A]. Get upstairs.
Move on the other side of the building and jump down. You can now put away the joypad and watch the first encounter with the Beautiful Beasts.