To start your 3-part chain quest you will have to talk to the High Elf Soldier right outside of the gates to the Brigand Camp:
This soldier will inform you that brigands have been harassing the area. If you accept this quest you need to kill five brigands.
There are brigands all over this area. However the easiest thing to do is wait until you are ready to move on to Sloeford. If you wait, you are likely to be higher level and will receive a better reward. You encounter a number of brigands on the way to Sloeford.
By the time you reach Sloeford, the High Elf Soldier should have the exclamation mark (!) above his head.
He can be found right outside the southwest entrance to the town of Sloeford.
After talking to him you complete your first part of this Chain-quest.
Some highwaymen are harassing the neighborhood. I should take care of them.
I think I have killed enough highwaymen now. That should teach them a lesson!
The guard in the village has another assignment for me.
After you talk to the High Elf Soldier, a question mark should appear over his head. If you talk to him, you have the opportunity to accept the second quest in this chain, Missing Patrol.