U.S. military installations in the Central Command region overseas moved overnight to Condition Delta, the highest level of alert, U.S. military sources said Wednesday.

CNN: U.S. at 'high alert' on anniversary of 9/11

About 9, 000 soldiers from the 3rd Infantry Division arrived in the Central Command region in two groups -- in September, 2002, and this January.

CNN: Pentagon releases Iraq troop rotation plan

There's a lot going on in my central command region.

NPR: Middle East Commander Fallon Steps Down

This fall, he takes over as chief of U.S. Central Command, where he will turn his attention to military operations in other parts of the region, including Afghanistan.

NPR: Petraeus: 'Long, Hard Slog' In Iraq