The death of al-Qaeda's leader leaves control of the terrorist organization in the hands of Osama Bin Laden's number two - Ayman Al-Zawahiri.
Reporting on TODAY this morning, NBC's Chief Foreign Correspondent Richard Engel told Matt Lauer, "Perhaps because of Al-Zawahiri's medical background, Matt, Ayman Al-Zawahiri has long expressed a keen interest in chemical and biological weapons."
Watch Richard's report above.









