▶ Watch Video: CBS News exclusive: Newly released video shows 9/11 hijacker with Saudi intelligence operative

While President Biden signed an executive order last fall to declassify 9/11 evidence, the families of some 9/11 victims say they had to go through the British courts to get records and videos seized two decades ago from an alleged Saudi government operative that have never been public until now.

“Why did it take 20 years for this information to see the light of day?” Brett Eagleson told CBS News senior investigative correspondent Catherine Herridge. 

He is leading a group of families fighting for the documents. He was 15 years old when his father, Bruce, was killed in the World Trade Center South Tower, and 20 years later, he wants his children to know what he calls “the secret of 9/11” and who was behind the plot to kill their grandfather. 

“Will the Justice Department now explain to the families and to America why they did not pursue charges against (Saudi national Omar) al-Bayoumi? And most astonishingly, why did this information come from the U.K. government and not our own FBI?” 

Boxes of evidence, including personal notes and video, were seized by British police. 

Less than two weeks after 9/11, boxes of evidence, including personal notes and video, were seized by British police from a home in Birmingham, England. 
Buried inside the trove is a home video from 2000, now being seen publicly for the first time. The event was described in 9/11 Commission records as a party at the San Diego apartment of Nawaf al-Hazmi and Khalid al-Mihdhar, the first two hijackers to arrive in the U.S. in January 2000.   
While the two hijackers apparently avoided the video camera at the party, a handful of frames captured Mihdhar in the kitchen. Along with Hazmi, their team would later commandeer Flight 77 that slammed into the Pentagon. 
The party’s host, Saudi national Omar al-Bayoumi, was arrested by British police less than two weeks after the attack that killed nearly 3,000 Americans in New York, the Pentagon and Shanksville, Pennsylvania. British police seized the videos and documents from Bayoumi.

Khalid al-Mihdhar, one of the first two hijackers to arrive in the U.S. in January 2000, is seen in the kitchen at a party. 

Three years after the attack, the 9/11 Commission said, “We have seen no credible evidence that he (Bayoumi) believed in violent extremism or knowingly aided extremists groups.”   
Though a newly declassified and heavily redacted FBI memo from 2017 stated, “In the late 1990s and up to September 11, 2001, Omar al-Bayoumi was paid a monthly stipend as a cooptee of the Saudi General Intelligence Presidency (GIP) via then Ambassador Prince Bandar bin Sultan….” 
The memo continued, “Allegations of al-Bayoumi’s involvement with Saudi Intelligence were not confirmed at the time of the 9/11 Commission Report. The above information confirms these allegations.” 
Another recently declassified FBI memo from the same year, citing source reporting, said, “There is a 50/50 chance Omar al-Bayoumi had advanced knowledge the 9/11 terrorist attacks were to occur.” 

The declassified records pertain to a long-secret investigation, code named “Operation Encore,” which centered on the two hijackers who lived in San Diego and who may have assisted them. 

The party’s host, Saudi national Omar al-Bayoumi, was arrested by British police less than two weeks after 9/11.

Retired FBI agent Danny Gonzalez, who worked on Operation Encore, told CBS News last fall that he believes Bayoumi was part of the hijackers’ U.S-based support network. 
“He helped them with apartments, he helped them with bank accounts,” Gonzalez told CBS News.   
Gonzalez and another former FBI agent, Ken Williams, are working on behalf of the families of some 9/11 victims in their litigation against the Kingdom of Saudi Arabia. Williams wrote a memo before 9/11 that warned potential terrorists were taking flight lessons in Arizona. 
Williams said, “He was also an employee of the government of Saudi Arabia.”   

According to a spokesman for the 9/11 families, the British files contain over 14,000 pages of documents, more than 20 hours of video and as many hours of audio interrogations of Bayoumi by British counterterrorism police.     
As part of their lawsuit seeking money from the Kingdom of Saudi Arabia, CBS News has learned that some of the 9/11 families said they subpoenaed the FBI for the Bayoumi records in 2018, adding only a fraction were provided by the bureau and are under seal, which means they will not be publicly released.   

Bayoumi is seen warmly greeting and embracing the American Muslim cleric Anwar al-Awlaki. 

Among the records released by British authorities was a notepad. As first reported by CBS News in August 2021, the FBI twice quizzed an American pilot in 2012 about the significance of the hand-drawn plane and mathematical equation.     

According to a sworn declaration for the court, the pilot said it might be used to view a target and then calculate the rate of descent to the target. “I shared with the FBI my opinion that there was a reasonable basis to believe that the drawing and equation were used as part of the preparations of the al Qaeda terrorists to carry out the 9/11 attacks,” Navy veteran and pilot Robert M. Brown said. 
In another video that is believed to be from before 9/11, Bayoumi is seen warmly greeting and embracing the American Muslim cleric Anwar al-Awlaki, who also supported the hijackers in San Diego and then in Virginia in the months before the 9/11 attack.    

Later killed in a CIA drone strike in 2011, Awlaki was the first American targeted for death by the agency as a senior leader of the al Qaeda affiliate in Yemen, which was responsible for failed plots including the attempted 2009 underwear bombing of a passenger jet on Christmas Day 2009. Awlaki is also blamed for the radicalization of Americans through his digital propaganda and the rise homegrown terrorism. 
“Al-Awlaki first comes in contact with the hijackers here in San Diego. He next comes in contact with them in Falls Church, Virginia,” Williams said. He believes the support network in southern California for the hijackers was mirrored in Virginia with Awlaki. 
“He follows them across the country, or they follow him across the country. … To what depth was he involved? To what extent was he involved? And we’re looking at that right now, in our work with the lawyers for the plaintiffs,” Williams said. 
Some of the 9/11 families are suing Saudi Arabia. The Saudis deny involvement, and the 9/11 Commission report found no connection. 
Bayoumi is believed to be living in Saudi Arabia. CBS News tried to reach him through the Saudi embassy. It did not immediately respond to our questions, but last fall said in a statement, “Any allegation that Saudi Arabia is complicit in the September 11 attacks is categorically false.” 

The FBI declined to comment. CBS News asked if the Bureau would consider re-opening its investigation into Bayoumi, and why the 9/11 plaintiffs had to go through the British courts to get the records and videos, rather than getting them from U.S. law enforcement.