Ayman al-Zawahri: the right-hand man of bin Laden during 9/11 attack

Washington: At about sunrise on Sunday, Al-Zawahri stood on the balcony of a house in Afghanistan's Kabul—that was the last time he was to do so.

The US intelligence that was hot on his heels had taken note of his daily practice of standing at the balcony at daybreak.

The Associated Press sourcing US officials reported that a US drone fired two Hellfire missiles at the al-Qaida leader - killing him instantly.

There ended the story of Ayman al-Zawahri, who helped Osama bin Laden plot the Sept. 11, 2001 attacks on the USA.

He also helped Al-Qaida survive and spread as the Western forces started cracking down on the terrorist outfit after the 9/11 attack in New York.

US authorities had long been trying to confirm his presence in Afghanistan.

Recently, Zawahri's wife and other family members moved to safe house in Kabul before Zawahri joined them, US official learnt this year.

US officials and leaders including Joe Biden had taken months before confirming his identity, according to the report.

Eventually, he was rounded about and killed in a precision attack.

The al-Qaida leader evaded US capture for 21 years after the suicide airliner attacks that razed to ground the twin towers in the New York.

The attack claimed a couple of thousand lives alongside upending several things that helped the world to be more peaceful.

Al-Zawahri was never seen without glasses on, slightly smiling - as in one photo of him showing him sitting beside bin Laden.

Born on 19 June, 1951, al-Zawahri came from 'comfortable family' and he was religious from boyhood.

Before long he immersed in a violent branch of Sunni Islamic revival seeking to replace government's Egypt and other Arab nations, according to AP.

As a young man he was an eye surgeon and found time to roam in Central and the Middle East.

He reportedly witnessed Afghan's fighting Soviet occupiers before he met with Osama bin Laden and other Arab militants.

He was among those captured and tortured following the assassination of President Anwar Sadat in 1981 and the experience, reportedly, further radicalized him.

Seven years later, al-Zawahiri was present when bin Laden founded al-Qaida, AP said.

Al-Zawahri spent years helping to achieve al-Qaida's Sept.11 attack and afterwards, he helped the organization survive Western crackdown on it.

He had been on the run after the 9/11 and was suspected to be living in Afghanistan.

However, al-Zawahri was rebuilding al-Qaida in the Afghan-Pakistan border region as well as being its supreme leader of branches in Iraq, Asia and Yemen, according to the report.

Al-Qaida went on with its targeted attacks even after 9/11 crackdown, and the attacks it carried out include those in in Bali, Mombasa, Riyadh, Jakarta, Istanbul, Madrid, London and beyond.

The 2005 attacks in London that killed 52 people were among al-Qaida's last devastating attacks in the West.