It's been a tough couple of weeks for al Qaeda. Since the successful Navy SEAL raid that killed Osama bin Laden, the terror network has suffered additional losses that analysts say are taking a heavy toll on the group.
Ilyas Kashmiri, al Qaeda's operational leader in Pakistan, was reportedly killed by a U.S. drone strike earlier this month (though al Qaeda hasn't confirmed his death, reports of which have been incorrect before). And last week, an al Qaeda leader in East Africa -- Fazul Abdullah Mohammed -- was killed by Somali forces in Mogadishu. Mohammed was the most wanted man in Africa.
Analysts and U.S. officials say the deaths have created a power vacuum.
"The organization is in a great deal of turmoil," a U.S. counterterrorism official told Foreign Policy. "It's trying to sort itself out with what's going on."
Bruce Hoffman, director of the Security Studies Program at Georgetown University, said Kashmiri and Mohammed were key operational figures, not easily replaced due to their long pedigrees of planning and executing attacks.
"They are especially important because they would have been looked on to plan and implement any acts of retribution [for bin Laden's death] from al Qaeda," he said. "Their killings knock them seriously off balance."
Of course, al Qaeda is well-known for its ability to replenish its ranks. Analysts like Hoffman and Evan Kohlmann, who has consulted with the U.S. government, see a few key names potentially emerging to fill the void.
1. Saif al-Adel
Born in Egypt in 1960 or 1963, according to the FBI. Currently believed to be hiding in Pakistan's tribal region.
Al-Adel was reportedly named the interim chief of Al Qaeda after bin Laden's death. After the 9/11 attacks, he fled to Iran, where he was eventually put under house arrest. In 2008, Iran swapped him for a diplomat taken captive by al Qaeda in Pakistan.
Signature attacks: Has played a hand in many al Qaeda attacks, allegedly dispatching Richard Reid, the shoe bomber, to meet Khalid Sheikh Mohammed; and aiding the 1998 attacks on the U.S. embassies in Africa.
2. Abu Basir al-Wahishi
Born in Yemen in 1976, according to Interpol.
Since 2009, al-Wahishi has been leader of al Qaeda in the Arabian Peninsula (AQAP), based in Yemen. According to Interpol, he claims to have been secretary to bin Laden prior to 2003. He escaped from a Yemeni prison in 2006.
Signature attacks: His group has been linked to the Fort Hood shooting and the attempted bombing by Umar Farouk Abdulmutallab of an airplane to Detroit on Christmas Day, 2009, among others.
3. Abu Yahya al-Liby
Born in Libya in 1973, according to the State Department.
Al-Liby was captured in 2002 and imprisoned at Bagram Air Force Base in Afghanistan, but escaped in July 2005. He's appeared in numerous propaganda videos since then.
Al Qaeda has named Liby one of its top field commanders in Afghanistan, according to the Washington Post.
4. Abdullah Ahmed Abdullah
Born in Egypt around 1963, according to the FBI.
Abdullah became one of al Qaeda's key money men after the September 11 attacks. The U.S. has a placed a $5 million bounty on his head.
Signature attack: Indicted for his alleged involvement in the 1998 U.S. embassy bombings in Africa.
5. The Americans: Anwar al-Awlaki, Omar Hammami, and Azzam al-Amriki (Adam Gadahn)
This trio of American-born militants have been heavily involved in trying to recruit other Americans to join al Qaeda and its affiliated groups. Awlaki, who is hiding in Yemen, is "spiritual leader" of AQAP and has used social media to communicate with potential recruits. Hammami, who grew up in Alabama with a Southern Baptist mother and a Syrian father, is now a leader of Somalia's al Shabab insurgency. He's also a prolific rapper. Amriki is thought to be in Pakistan, heavily involved in releasing propaganda material targeted to Western audiences.
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