The death of Ayman al-Zawahiri in a drone strike means that all of the 9/11 plotters are now either in prison or dead.
He was finally tracked down to a house owned by the Taliban in Kabul, Afghanistan by US intelligence operatives who had kept an eye out for the resurfacing of al-Qaeda members in the wake of the Taliban seizing power in the country.
Agents were able to verify that al-Zawahiri was living in the house and planned out his regular routine, including noticing that he spent a lot of time on the building's balcony.
US president Joe Biden confirmed that a drone strike on the balcony killed al-Zawahiri, no other casualties have yet been reported.
There were eight plotters behind the 9/11 attacks, and the killing of al-Zawahiri marks the moment that all of them have ended up either dead or captured.
The highest profile plotter was Bin Laden himself, who became the world's most recognisable terrorist in the wake of the 9/11 attacks.
He was killed in 2011 by a US Navy SEALs raid on a compound in Pakistan and his body was buried at sea to ensure it didn't become a shrine for other terrorists.
Al-Zawahiri was seen as Bin Laden's right hand man and took control of al-Qaeda following his death, he was able to elude capture for more than 20 years before his was tracked down in a six-month operation.
The first plotter to be caught was Mohammed al-Qahtani, who was apprehended in January 2002 trying to cross the border between Afghanistan and Pakistan and sent to Guantanamo Bay, he was released to Saudi Arabia earlier this year after he was deemed to no longer be a threat.
The next to be captured was Ramzi bin al-Shibh, caught in Karachi, Pakistan exactly a year on from the 9/11 attacks, he is currently incarcerated in Guantanamo Bay.
Khalid Sheik Mohammed and Mustafa al-Hawsawi were captured together in March 2003 during a joint raid between CIA and Pakistani intelligence, Guantanamo Bay was also the destination for both of them.
A month later Ammar al-Baluchi and Walid bin-Attash were captured in Karachi by Pakistani authorities and joined their fellow 9/11 plotters in Guantanamo Bay.
Within less than two years six of the eight plotters behind the 9/11 attacks had been captured, though Bin Laden and al-Zawahiri would prove more elusive before both were tracked down and killed.
If you have a story you want to tell, send it to UNILAD via [email protected]
- Man who checked hijackers onto Flight 77 on 9/11 says it's haunted him ever since
- Reverend behind the biggest intentional civilian death in American history before 9/11
- Al-Qaeda bomb maker-turned MI6 spy described what it was like meeting Osama Bin Laden
- American woman who went from local teacher to ISIS leader now faces 20 years in prison