The C.I.A. has released dozens of intelligence documents sent to Presidents Bill Clinton and George W. Bush before the Sept. 11 attacks.
The materials detail what the agency knew about Al Qaeda in the years leading up to 2001.
The release follows long-standing calls for greater transparency around pre-9/11 intelligence.
The documents include briefings and assessments provided to both administrations during a period of rising threat.
They show that Al Qaeda was repeatedly identified as a serious national security concern.
Intelligence officials tracked the group’s activities, leadership, and plotting across multiple regions.
The records also indicate that warnings about possible attacks were shared with senior policymakers.
However, the documents do not establish that specific details of the Sept. 11 plot were known in advance.
The C.I.A. said the release is part of its effort to declassify historical records of public interest.
Historians and researchers are expected to review the materials for new insights into pre-attack decision-making.
The disclosure adds to the public record on how the U.S. government assessed terrorist threats before 2001.
