On the level Metropolis, near the area where the player fights a trio of Wraiths (the Marine command post), there are public bulletin panels scattered about with public messages or "Citizen Alerts" to civilians. You can find one by following the road which curves around in a detour to the left. There are two variations of the sign, each with a different message concerning the battle with the Covenant. These signs are similar to the four that are visible in the Halo 2 E3 Demo, when Master Chief operates the turret and after one of the Marines on the radio says "Hostiles right." It is unknown if the messages on the boards are the same as in the final game. One of the variations of the sign is a message from Earth Secretary of Defense Paul Murphy Russel, imploring the youth of New Mombasa to enlist in their local "freedom fighter brigade" to fight the Covenant. The other variant is a message from Earth Minister of Information David Dockmaster Dunn, urging civilians to "please do your part by reporting to the nearest evacuation zone." Unlike most other signs on the level, these signs are destructible and will explode violently (the way they do in the Halo 2 E3 Demo). This explosion will launch a ghost rather far if the ghost is pressed up against it.
- These signs display messages on both sides, despite the fact that one side faces a wall.