Hamza bin Laden is know to have spent many years after the attacks in Iran, where he and dozens of other family members of the 9/11 plotters were guarded by senior Iranian intelligence and military officials. The group was at times in effect under house arrest and other times free to move around. Hamza was mentored in Iran by Abu al-Khayr al-Masri, who was deputy to al-Zawahiri after the death of Osama bin Laden. Al-Masri was released by Iran and taken to the Turkish border, from where he crossed into Syria. He was killed by a US drone in Idlib province in February 2017.
Some reports at the time suggested Hamza had also travelled to Syria. However, he is believed to have instead made his way to the tribal territories between Afghanistan and Pakistan.
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