When you begin this mission, you see none other than Doned walking by. Marche calls out to Doned, who runs away and tells a group of Bangaa that you are there and you are the kid with the bounty on his head. So it was Doned who tipped off the clan in the previous mission??
In this battle, there is a Bishop, a Dragoon, a Defender, a Gladiator, a White Monk, and two Soldiers. The Bishop can heal the enemy units, so get rid of him to speed up the battle. The other enemies aren't too difficult to deal with. The Defender has Drop Weapon, so you might want to disable and KO him soon to avoid having your weapons unequipped. The Soldiers can provoke your units into Berserk, which can be problematic. With the others, just take them on one at a time and you'll be fine.