A bulletin recently sent by the FBI to about 18,000 police organizations warned that terrorists may use almanacs to “assist with target selection and pre-operational planning.” The possession of these reference books should be noted during searches, traffic stops, and other investigations, said the FBI, especially if annotations are made in the pages.
The bulletin notes that use of almanacs may be innocent, but someone exhibiting suspicious behavior in addition to having an almanac “may point to possible terrorist planning.”
The FBI urges police to report such discoveries to the local U.S. Joint Terrorism Task Force.