WASHINGTON • The US has officially listed a son of Osama bin Laden as a "global terrorist", and warned that the younger man, who has called for attacks around the world, poses a risk to national security.
Hamza bin Laden, who has pledged to take up his father's violent mantle and avenge his death, is "actively engaged in terrorism", the State Department said on Thursday, putting his age at 27.
Placing Hamza on the government list, formally known as the Specially Designated Global Terrorist list, gives officials legal tools to isolate him and hamper his movements and transactions.
It is also a reminder of the continued terrorism campaign waged by Al-Qaeda, which was founded by Osama, and its affiliates, and of its aim to recruit and groom a new generation of militants.
Hamza, one of Osama's 23 children, was named a member of the terrorist group in 2014 by his father's successor, Ayman al-Zawahri. Since then, in a series of recorded messages, Hamza has called for attacks on Western capitals and also warned Americans that they would be "targeted in the United States and abroad", according to the State Department.
Last year, in a video released by Al-Qaeda's media outlet As-Sahab, Hamza pledged to avenge Osama's death, warning Americans that if they believed the killing of his father by US forces in 2011 had "passed without punishment, then you thought wrong".
From a young age, Hamza had expressed an interest in joining his father's terrorist campaign.
As a boy, he appeared in propaganda films, and documents found after his father's death indicate that the young man was being groomed for an Al-Qaeda leadership role.
In 2009, in a letter discovered at Osama's hideout in Pakistan and eventually reported by American officials, Hamza wrote: "My beloved father, I was separated from you when I was a small child, not yet 13, but I am older now, and have attained manhood."
"But what truly makes me sad," he added, "is the mujahideen legions have marched and I have not joined them."
A letter said to have been written by Osama in 2010 called his son "very sweet and good" and also described his ardour to join Al- Qaeda's fight.
"He comes back to me asking me that he should be trained and participated in giving," the letter read. "He does not want to be treated with favouritism because he is the son of 'someone'. I promised him to plan some safe training for him: firing arms and with various weapons."
Hamza, whose mother is Khairiah Sabar, is one of the few children of Osama to openly express a willingness to follow in their father's footsteps.
The US government incorrectly said he was among the dead in the raid that killed his father, later issuing a correction to say that another son, Khalid, had been killed and that Hamza had not been in the home at the time.
Khairiah, a native of Saudi Arabia, was among those captured in the raid in Abbottabad, Pakistan. She was later released. Hamza is her only child.