Authorities continue to refer to Hasan, 39, as the only suspect in the shootings, but they won't say when charges would be filed and have said they have not determined a motive. A spokesman for Army investigators did not immediately respond to calls and e-mails seeking comment Monday.
"Nidal Hassan (sic) is a hero," Awlaki said. "He is a man of conscience who could not bear living the contradiction of being a Muslim and serving in an army that is fighting against his own people."
Two U.S. intelligence officials told The Associated Press the Web site was Awlaki's. They spoke on condition of anonymity to discuss intelligence collection. Awlaki did not immediately respond to an attempt to contact him through the Web site.
Awlaki is a native-born U.S. citizen who left the United States in 2002, eventually traveling to Yemen. He was released from a Yemeni jail last year and has since gone missing. He is on Yemen's most wanted militant list, according to three Yemeni security officials.
The officials say Awlaki was arrested in 2006 with a small group of suspected al-Qaida militants in the capital San'a. They say he was released more than a year later after signing a pledge he will not break the law or leave the country. The officials spoke on condition of anonymity because of the sensitivity of the issue.
The Falls Church mosque is one of the largest on the East Coast, and thousands of worshippers attend prayers and services there every week.
The London Telegraph first reported the potential link between Hasan and the mosque.
Command Sgt. Maj. Arthur L. Coleman Jr. said Monday that reopening the center is an important step in returning the Army post to normal. Cone said the post stepped up security, including suspending visits by the public, largely to reassure the population that the sprawling base is safe and won't "become a battlefield."