(CNN)Here's a look at the life of al Qaeda leader Ayman al-Zawahiri.
Birth date: June 19, 1951
Birth place: Egypt
Birth name: Ayman Muhammad Rabi al-Zawahiri
Father: Rabie al-Zawahiri, professor of pharmacology
Mother: Umayma al-Zawahiri
Marriages: Unknown publicly
Children: Unknown publicly
Education: Cairo University, 1974, master's degree in surgery, 1978
Acted as Osama bin Laden's personal physician.
Zawahiri comes from a distinguished Egyptian family, according to the New York Times. His grandfather, Rabia'a al-Zawahiri, was an imam at al-Azhar University in Cairo. His great-uncle, Abdel Rahman Azzam, was the first secretary of the Arab League.
The US State Department is offering a reward of up to $25 million for information leading directly to the capture of Zawahiri.
A June 2021 United Nations report suggests his location as somewhere in the border region of Afghanistan and Pakistan, and that he may be too frail to be featured in propaganda.
1970s - Zawahiri and the Egyptian Islamic Jihad work to overthrow Egyptian President Anwar Sadat and establish an Islamic state.
1980s - Joins the Mujahedeen who are fighting Soviet forces occupying Afghanistan.
1981 - Zawahiri is among hundreds of suspects arrested after the assassination of Sadat. He is not charged in connection to the assassination, but is sentenced to three years in prison for weapons possession.
August 6, 1998 - A fax from Zawahiri's group is sent to an Egyptian newspaper declaring that the Egyptian Islamic Jihad is seeking revenge against the US for the arrest of several of its members.
August 7, 1998 - Suicide bombers attack the US embassies in Kenya and Tanzania.
1998 - The Egyptian Islamic Jihad, led by Zawahiri, and al Qaeda merge. Zawahiri and bin Laden issue a fatwa, published in an Arab newspaper, stating that Muslims should kill Americans around the world.
1999 - Zawahiri is indicted for the 1998 US Embassy bombings in Kenya and Tanzania. He receives a death sentence, in absentia, from an Egyptian court, for an alleged plot against US interests in Albania.
December 2001 - Zawahiri's wife and three of his children are killed in a US attack on the family's residence in Afghanistan.
June 8, 2011 - A video of Zawahiri eulogizing bin Laden is released.
June 2011 - A US counterterrorism official tells CNN he believes that Zawahiri is the new leader of al Qaeda.
October 2012 - In a video posted on jihadist websites, Zawahiri praises the kidnapping of Warren Weinstein, an American citizen in Pakistan. Weinstein, a development expert, was abducted in 2011 from his home in Lahore, Pakistan. Zawahiri encourages followers to kidnap more westerners.
April 2014 - Audio of a two-part interview purportedly with Zawahiri is posted on a radical Islamist website.
August 2015 - In an audio recording, a person claiming to be Zawahiri states that al Qaeda is aligned with the new leader of the Taliban, Mullah Akhtar Mohammad Mansour.
September 2015 - Zawahiri releases audio messages in which he suggests al Qaeda and ISIS should unify, even as he declares that the caliphate established by the Islamic State is not legitimate.
May 2016 - A man purporting to be Zawahiri pledges allegiance to the new Taliban leader, Mawlawi Haibatullah Akhundzada, in a recently released audio statement. "As the Emir of al Qaeda jihadist group, I present our allegiance to you," says a man's voice, which sounds like Zawahiri's
May 13, 2018 - In response to US President Donald Trump moving the US embassy from Tel Aviv to Jerusalem, in a video message Zawahiri calls for resistance by Palestinians and a jihad against the US.
February 5, 2019 - Zawahiri's speech, "The Way of Salvation," is released. In the video, Zawahiri urges supporters to unite against enemies, including Shiite Muslims, Americans, Russians, French and Chinese.