Canadian Invasion Group of tribals behind a roadblock. They mistake you for canadians and start firing. Snipe them all. The much talked about acid supersoaker is on one of them. The ammo for it is rather rare, and I would suggest saving it for the harder enemies.
Range is short, too.
Keep your eyes peeled. They're devious, these Canadians. I heard that Canadia started the great war. The moronic robot has 30 or so rounds of 7.62. Reference to a movie, the Matrix.