Now, the Department of Homeland Security is warning that terrorists could exploit the anniversary.
President Joe Biden on Friday directed the declassification of certain documents related to the attacks, a supportive gesture to victims' families who have long sought the records in hopes of implicating the Saudi government.
The order directs the Justice Department and other executive branch agencies to begin a declassification review, and requires that declassified documents be released over the next six months.
Late last week, the Department of Homeland Security and the FBI warned that foreign terrorist organizations could exploit the anniversary.
The agencies said in a bulletin sent to law enforcement leaders, obtained by ABC News, that they are not currently aware of any specific and credible threat related to the date.
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