A day after the 23rd anniversary of the Sept. 11 attacks, the FBI put out a call to the public for information on the whereabouts of a once-close associate of Usama bin Laden for his alleged involvement with al Qaeda.

Hamza Al Ghamdi, who served as a trusted member of bin Laden's security detail in the period leading up to the 2001 attacks, held significant roles within the terror network and served in various conflict zones over the years, Tony Molloy, the special agent in charge of the FBI's Joint Terrorism Task Force in the bureau's New York office, told Fox News Digital. 

"The FBI has information dating back to his affiliation in fighting violent and waging violent Islamic extremist jihad in foreign conflict zones dating back to the late '90s," Molloy said.

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Hamza Al Ghamdi, a citizen of Saudi Arabia, is wanted for questioning in connection with his membership in al Qaeda. He once served on the security detail for Usama bin Laden, the FBI said. (FBI)

Ghamdi is wanted for questioning in connection with his alleged membership in al Qaeda, during which he served as bin Laden's personal bodyguard and other roles. 

"We know through his affiliation and his associations that put him in direct contact with those senior leaders that he likely has information of historical relevance to our investigations and our current investigations into al Qaeda operations and attacks globally in the last 20 years," Molloy said. 

Like bin Laden, Ghamdi is a native of Saudi Arabia and fought alongside the deceased terror leader against Russian troops in Afghanistan in the 1980s, the FBI said. He also participated in terrorist attacks in Tajikistan in the early 1990s and operated an al Qaeda guesthouse in the Afghan capital of Kabul, authorities said. 

Hamza Al Ghamdi has allegedly participated in armed jihad in various conflict areas, including Afghanistan and Tajikistan. (FBI)

In December 2001, he fought in the last battle of Tora Bora, a U.S. military operation in eastern Afghanistan aimed at capturing or killing bin Laden, who was believed to be hiding out in caves. Bin Laden eventually evaded capture until he was killed by U.S. forces in 2011 while hiding out in Pakistan. 

Ghamdi is believed to be somewhere in Afghanistan, possibly near the country's border with Pakistan, said Molloy. The State Department is offering a $5 million reward for his capture. 

"He tends to operate in non-permissive locations, which makes it difficult to locate and question him," Molloy said. 

Far from being just a member of al Qaeda, Ghamdi worked with the group's senior leaders, including Ayman al-Zawahiri, who played a role in the Sept. 11 attacks and was killed in a 2022 U.S. drone strike in Afghanistan. 

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Al Qaeda leader Ayman al-Zawahiri, who was killed in a CIA drone strike in Afghanistan, appears in an undated FBI Most Wanted poster. (FBI/Handout via Reuters)

"His death deals a significant blow to al Qaeda and will degrade the group's ability to operate, including against the U.S. homeland," President Biden said at the time. 

Biden said Zawahiri also masterminded other attacks against the U.S., including the October 2000 suicide bombing of the USS Cole in Yemen, which killed 17 U.S. sailors, and the 1998 attacks on the American embassies in Kenya and Tanzania, which killed 223 people. 

Damage to the U.S. destroyer US Cole following a terrorist attack in Yemen on Oct. 12, 2000. The attack killed 17 sailors and injured 40 others. (Reuters)

Despite the 23 years since the Sept. 11 attacks, the FBI is still looking to apprehend those involved, the agency said. 

"We have not forgotten," Christie M. Curtis, acting assistant director in charge of the FBI’s New York City Field Office, said in a Thursday news release. "Twenty-three years later, the FBI is still seeking justice for the victims of the September 11th attacks by continuing to seek those who desire to harm us."

Usama bin Laden's infamous "Letter to America" justified terror attacks on the United States. (CNN via Getty Images)

The FBI has noted that Ghamdi is not the same Hamza al Ghamdi who was one of the terrorists on United Airlines Flight 175 that took over the plane and crashed it into the World Trade Center in New York City. 

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Molloy said people like Ghamdi need to be taken off the "global jihad battlefield."

"The American people expect it. The victims deserve it and it will make us all safer," he said.