On May 2, 2011, Navy SEALs shot and killed al Qaeda leader and September 11 mastermind Osama bin Laden in his home in Abbottabad, Pakistan. It was a raid made especially daring by the fact that there was only a 50-50 chance the terrorist leader was there. After his death, these are five of the top al Qaeda leaders who pose a clear and continuing threat of an attack within the US, according to US intelligence and counterterrorist officials.
Ayman al-Zawahri - Egyptian cleric Ayman al-Zawahri took over the organization, after Osama bin Laden's killing last year by Navy SEALs. Presumed hiding in Pakistan, Zawahri has released a near-record number of propaganda videos since the bin Laden raid, exhorting followers to violence.
Abu Yahia al-Libi - The Libyan militant, as his name implies, is now the group's de facto No. 2 moving up a notch in al Qaeda's hierarchy after the bin Laden raid. A key al Qaeda propagandist whose video appearances outnumber those by leader Zawahri, he escaped a high-security US prison in Bagram, Afghanistan, in 2005.
Mullah Mohammed Omar - Leader of the Taliban, Afghan Mullah Omar has sheltered al Qaeda during the Taliban rule and since. Thought to be hiding in Quetta, Pakistan, Omar continues to command the militant forces who work together with al Qaeda, responsible for killing some 1,500 US troops in Afghanistan since 2001.
Nasser al-Wahishi - Once Osama bin Laden's aide-de-camp, Wahishi commands Yemeni affiliate al Qaeda in the Arabian Peninsula, or AQAP, the group US counterterrorist officials warn is most capable of launching an attack on US soil. AQAP has established a de facto safe haven in southern Yemen, beating back Yemeni forces that have been consumed with fighting a tribal and political revolt in the wake of the Arab Spring.
Ibrahim Hassan al-Asiri - Chief bombmaker for al Qaeda in the Arabian Peninsula, responsible for building the underwear bomb used to try to bring down a Detroit-bound jetliner on Christmas 2009 and the printer-cartridge bombs intercepted in US-bound cargo planes a year later. US intelligence officials say he has resurfaced recently in Yemen, after months in hiding following the death by drone strike of American-born firebrand AQAP cleric Anwar al-Awlaki last fall.