The United States on Thursday announced that it will offer a reward of up to $1 million (over Rs 7 crore) for information on Hamza bin Laden, one of the sons of former al Qaeda leader Osama bin Laden.

The State Department asked for any details leading to the identification or location of bin Laden, who it said was “emerging as a leader” in the al Qaeda.

“Since at least August 2015, he has released audio and video messages on the Internet calling on his followers to launch attacks against the United States and its Western allies, and he has threatened attacks against the United States in revenge for the May 2011 killing of his father by US service members,” the US Department of State said in a press release.

Hamza bin Laden is the son of Khairiah Sabar, one of Osama bin Laden’s three surviving wives. Sabar was living with her husband when he was killed in Pakistan’s Abbottabad in a military operation in 2011, a decade after the September 11 attacks. Hamza bin Laden, who is suspected to be around 30 years old, has reported to have been living in Pakistan, Afghanistan, Syria and even Iran in the past.

Osama bin Laden’s wives and other children have gone back to Saudi Arabia, where they were given refuge by the former Crown Prince Mohammed bin Nayef. They reportedly still stay in touch with Laden’s mother, Alia Ghanem.

In August, reports emerged that Hamza bin Laden had married the daughter of Mohammed Atta, the chief hijacker in the 9/11 terror attacks in the United States. He is considered the second-in-command to current leader Ayman al-Zawahiri in the al Qaeda. Bin Laden has reportedly threatened to exact revenge against the United States for his father’s death. In January 2017, the US added him to its counter-terrorism list, prohibiting its citizens from doing business with them.

“As a result of the designation, all of Hamza bin Laden’s assets based in the United States or in the possession or control of US persons are frozen, and US persons are generally prohibited from engaging in transactions with him,” the US State Department added.