By Carlo Muñoz - 09/12/12 04:38 PM EDT
Sen. Bill NelsonBill NelsonFederal agency under fire for selling recalled cars Senators offer renewed hope of ending hotel booking scams Yahoo hack spurs push for legislation MORE (D-Fla.), a member of the Senate Select Committee on Intelligence, said Wednesday the embassy attack could be tied to al Qaeda operatives in Libya seeking retribution for the death of the terrorist group's second-in-command.
“These murders have the markings of revenge by al Qaeda," Nelson said in a statement.
Al Qaeda leader Ayman al-Zawahiri circulated an Internet video Monday night urging Libyans to take action against American positions inside the country as revenge for Abu Yaha's death, according to Nelson.
Al-Zawahiri assumed control of the terror group last May, after U.S. special operations forces killed Osama bin Laden during a raid on his compound in Abottabad, Pakistan.
In response to the embassy attack, Nelson is calling for congressional hearings to "to immediately investigate what role al Qaeda or its affiliates may have played in the attacks ... and to urge appropriate action."
President Obama already has ordered increased levels of security at all U.S. embassies in the wake of Wednesday's attack.
The Pentagon has deployed a Marine Corps units to Libya to secure the embassy and provide additional protection for American diplomats still stationed in the country.
The Marines units en route to Libya are part of the U.S. military's Fleet Antiterrorism Security Team (FAST), whose sole mission is to serve as a quick reactions force to conduct counterterrorism and to reinforce security at U.S. embassies.