Finish the first part, protecting the ambassador. Once done, you will hear, "Now go to room 12 and wait for him to arrive". Instead of doing that, go to the man who locks himself out. He is the first civilian that you see. Go to the courtyard. Once you get to the entrance to the courtyard, make a quick left. You will see a ledge. Jump onto it. Note :It breaks very fast -- quickly jump to the other ledge where the windows are open. Be careful or you will fall. Once inside, check it out. Note: Jump into the window with the clothes line on it.