Original sentence: , simultaneously hijacked four U.According to the official 9/11 Commission Report, nineteen men affiliated with Osama bin Laden and Al-Qaeda, a loose network of Sunni Islamist terrorists
Edited sentence: According to the official 9/11 Commission Report, nineteen men affiliated with Osama bin Laden and Al-Qaeda, described by  as a loose network of Sunni Islamist terrorists, simultaneously hijacked four U