Woohoo, I found one little bastard in camp angel :D
Somewhere around Cardinal.
Found two!
Mission 1 - I targeted the guy when I was hitting U key all the time about halfway through the mission. I had to deviate from my patrol path about half of a kilometer to catch him though.
Mission 2 - Take a peek "under" the platform.
Mission 3 - Didn't find him, but saw it in the mission logs - arriving about 6 minutes into the mission.