WASHINGTON -- Ayman al-Zawahiri, the man tipped to succeed Osama bin Laden as head of al-Qaida after years as second-in-command, is often described as the terror network's ideologue-in-chief.
He has also been al-Qaida's main spokesman in the past few years, issuing dozens of audio and video statements since the Sept. 11, 2001 terrorist attacks as U.S. troops scoured Afghanistan and Pakistan for bin Laden.
An eye surgeon by training al-Zawahiri, 59, was born into a middle-class family of doctors and academics from the northern Egyptian governorate of al-Beheira and became politically active at a young age.
He joined Egypt's Muslim Brotherhood, the country's oldest Islamist organization, as a teenager and later the more radical Egyptian arm of Islamic Jihad, which was behind the 1981 assassination of Egyptian president Anwar el-Sadat.
Al-Zawahiri was one of hundreds of militants arrested over the killing of Sadat, which was triggered by the president's signing of a peace deal with Israel. He spent three years in prison on charges of weapons possession -- an experience that is said to have radicalized him.
On his release from prison in 1985 he left for Saudi Arabia and from there to Pakistan and Afghanistan, where he served as a doctor during the Soviet occupation and recruited young people into jihad.
Al-Zawahiri switched his attention back to Egypt in the mid-1990s, where Islamic Jihad led a campaign to topple the government and install an Islamic state. While his attempts failed, the group has been blamed for the deaths of scores of Egyptians and was also blamed for an attack on tourists in Luxor in 1997.
For his role in the campaign, al-Zawahiri was sentenced to death in absentia by an Egyptian court.
In 1998, he merged forces with bin Laden's and other Islamist groups calling for jihad against "Jews and Crusaders."
Al-Zawahiri is believed to have exerted considerable influence over al-Qaida strategy, convincing bin Laden to broaden his sights beyond ending the US military presence in bin Laden's native Saudi Arabia to global jihad, or holy war.
That year saw al-Qaida terrorists mount simultaneous attacks on the U.S. embassies in Kenya and Tanzania, killing 223 people. Bin Laden and al-Zawahiri were indicted for the attack in the United States.
In 2001, al-Zawahiri was named No 2 after bin Laden on Washington's most-wanted list, with a 25-million-dollar reward offered for information leading to his arrest.
He is believed to have survived at least one attempt on his life by the U.S. since then.
From hiding, believed to be in Pakistan, he has repeatedly spoken out, to taunt the United States and launch diatribes against Washington and Israel.
More recently, al-Zawahiri commented on the uprisings in the Arab world, which have been hailed as a triumph for pro-democracy movements over fundamentalism.
In a video posted online in mid-April he welcomed the fall of Egyptian president Hosni Mubarak and called for Arab armies to intervene in the conflict in Libya to topple leader Moammar Gadhafi, lest the Western intervention turn into an invasion.
Whether al-Zawahiri can impose himself as a successor to bin Laden at the head of the disparate al-Qaida network is unclear.
A senior U.S. official on Monday said he believed al-Zawahiri was "far less charismatic (compared to bin Laden) and not as well respected within the organization."
The official said he was going on "comments from several captured al-Qaida leaders."
(c) 2011, Deutsche Presse-Agentur GmbH (Hamburg, Germany).
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