A timeline of events on September 11, 2001 and beyond.
9/11 flight numbers 93 and 175 were accidentally used for two Continental Airlines flights. United apologized but would not explain how the error happened.
Muslim cleric Anwar al-Awlaki is thought to be connected to at least three alleged terrorist attacks, including the Fort Hood shootings, the Christmas Day bombing attempt on an airliner, and the May 2 Times Square bomb.
Alleged Fort Hood shooter Major Nidal Malik Hasan had ties to US-born militant Moslem cleric Anwar al-Awlaki, a leading figure seeking to recruit English speakers to violent jihad.
A Christian Science perspective.