This mission is basically a battle against Barricade. In the beginning you go to the house pinpointed on your radar. When you arrive you will see Barricade, who says he's already got what you came for. You chase him down until he goes to the bridge. Pick up some health before you fight him, because the police have already shot at you and you'll need all the health you can get. You attack him until his health is drained. Unlike other bosses, he will escape.