Al-Qaeda has reportedly appointed Ayman al-Zawahri as its leader following last month's killing of long-time chief Osama bin Laden.
The terrorist network's general command made the announcement "after consultations" in a statement posted on a website known for its links to Al-Qaeda.
Under the new leadership of Zawahri, the group vowed to continue to fight a jihad, or holy war, against what it called "conquering infidels, led by America and its stooge Israel" and whoever supports them.
The statement stated its support for this year's popular uprisings in North Africa and the Middle East, and called on all Muslims to "rise up and continue the struggle, persistence, and devotion until all the corrupt and oppressive regimes imposed by the West are gone."
U.S. State Department spokeswoman Victoria Nuland said it "barely matters" who the new leader of the terrorist group is.
However, Admiral Mike Mullen, the chairman of the Joint Chiefs of Staff, said that the United States will seek to hunt down and kill the new Al-Qaeda leader, just as it did bin Laden.
Patryk Pawlak, a research fellow at the European Union Institute for Security Studies in Paris, calls Zawahri a "divisive figure" in the Al-Qaeda network. He says Zawahri's leadership could mean a further decentralization of Al-Qaeda, which some experts say has operated tactically without bin Laden for years.
"Al-Zawahri is not perceived as such a charismatic leader as bin Laden was," Pawlak says. "One of the major features that made bin Laden so powerful was exactly that he was able to get people behind him quite well and he enjoyed pretty big support on the side of different terrorist organizations from the Al-Qaeda movement."
He says the fact that it took a month and a half for the announcement of Zawahri's promotion to replace bin Laden "is a proof to the fact that actually there was not much agreement concerning [Zawahri's] leadership on the Al-Qaeda side."
Trying To 'Terrify'
Bin Laden was killed by U.S. forces in a covert operation in the Pakistani garrison town of Abbottabad on May 1-2.
Rahimullah Yusufzai, the Peshawar-based executive editor of Pakistan's "The News International," told RFE/RL's Radio Mashaal that he did not expect many changes with Zawahri at the helm.
Yusufzai said Zawahri was Al-Qaeda's "second important leader" and there was no one else to take over after bin Laden's death. "The decision took some time and the reason may be that the organization is not as organized and even they are facing hardships in continuing their activities in this region," he added. "I think there will be no change in Al-Qaeda policy because Zawahri was making the policies and most of the statements when bin Laden was alive."
In a video eulogy to bin Laden released earlier this month, Zawahri warned that bin Laden would continue to "terrify" the United States from beyond the grave.
"The sheikh has departed, may God have mercy on him, to his God as a martyr and we must continue on his path of jihad to expel the invaders from the land of Muslims and to purify it from injustice," Zawahri said.
The Egyptian-born had been bin Laden's second in command for years and widely anticipated to replace him.
Thought to be in his late 50s, Zawahri now sits atop the United States' most-wanted-terrorist list, with a $25 million reward offered for information leading to his capture.
U.S. prosecutors have indicted him for his suspected role in the 1998 bomb attacks on the U.S. embassies in Tanzania and Kenya.
His whereabouts are not known, but security analysts have suggested Zawahri is most likely to be hiding in the Afghan-Pakistani border region.
Zawahri is the son of an upper-middle-class Egyptian family of doctors and scholars. He studied at Cairo University and qualified as a doctor.
He was jailed for three years in Egypt for militancy and later met bin Laden in the mid-1980s, when both were supporting the mujahedin fighting the Soviet occupation of Afghanistan.
In the 1990s, he took over the leadership of the Egyptian Islamic Jihad group, whose original primary goal was to establish an Islamic state. The group later merged with Al-Qaeda.
In 1999, an Egyptian military court sentenced Zawahri to death in absentia.
Zawahri followed bin Laden to Sudan and then back to Afghanistan, where they found a safe haven under the radical Taliban regime.
based on agency reports