Secret Service

Relatively straightforward acheivement - just shoot and destroy 10 fire extinguishers.

I found they started to appear on level 2 Coup D'Etat. As you would assume they are bright red and dotted on the walls every so often. Just make sure when you shoot them, you stay back as they do tend to explode.

I had completed this by level 3, and the level where you start to head down to the tunnels (Urban Legend I believe), there is about 7-8 right at the start before you meet any enemies.