From Halopedia, the Halo wiki
The Citizen Alert was a series of propaganda messages released by the United Earth Government to reassure the civilian population during the Battle of Earth in 2552. In New Mombasa, two Citizen Alert messages were displayed on electric message boards.
One of the messages is from Earth Secretary of Defense Paul Huphy Russel, imploring the youth of New Mombasa to enlist in their local "freedom fighter brigade" to fight the Covenant. The other 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."
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