Alright so I shot all the people outside the main gate and destroyed the alarms there and the one in the building on top of the gate. HOW THE HELL DO I PASS IT FROM HERE? I've played the level about 50 times and I never can pass. I go in the first building on the right and shoot the guy there, go back out and then through the gate on the right. Then I go into the building on the left, duck down so I'm not seen by the guy by the last alarm, and shoot that guy. I've been all over and I cannot find the snooper rifle and I cannot seem to stow away into the truck without being noticed. Anyone who can help feel free to talk to me

snooper is round the edge of lake before entering compound, kill everyone bar last gaurd, (did you get the one on the tower?) sneak round the edge of compound to platform with boxes then into truck.

And if you want a secret, there is a box that you can destroy. In the box is some ammo stuff.