After the introduction cutscene, you'll take control as Damon Baird. Head down the path until the buildings begin to crumble and collapse. Head left, towards a set of stairs that lead to a flame-filled area. Kick the sofa out of your way to proceed. Kick the following door in and proceed to the courtyard. Locust will appear once you reach the tree on fire. Around 3-4 Grubs will spawn, with the possibility of Wretches appearing as well. An alleyway to the left of the burning tree will yield ammo, if needed. The Declassfied Mission can be found nearby.