Mohamed Atta , the ringleader of the attacks , and a fellow hijacker , Abdulaziz al-Omari , arrived at Portland International Jetport at 05:41 Eastern Daylight Time on September 11 , 2001 .
Mohamed Atta , a member of terrorist group al-Qaeda and leader of the attacks , and another hijacker , Abdulaziz al-Omari , flew together from Portland , Maine to Boston early on September 11 , 2001 .