1) Scientists at a nearby laboratory reported that their zombie experiment went wrong, causing a large zombie outbreak 50 miles away that is spreading rapidly towards Fort Dawn.
2) The zombie outbreak is now only 10 miles away from Fort Dawn and growing faster and more aggressive, with the potential to reach them within an hour in a worst case scenario.
3) General Marshall warns everyone at Fort Dawn about the situation and orders them to arm themselves, as they must work to warn others and fight off the zombies to survive and prevent the end of humanity.