From the Associated Press:
HUNTSVILLE, Ala. (AP) — A military installation in Alabama says in a tweet it is on lockdown amid reports of a possible active shooter.
Redstone Arsenal near Huntsville tweeted Tuesday that it is on lockdown.
The base said on its Facebook page Monday that it would be conducting an active shooter training exercise this week.There's no immediate word from base officials about whether the threat is of an actual shooter or merely part of a scheduled exercise.
More information as it comes.