Last week, I posted a link to that battlestaff directive from Tinker AFB, Oklahoma, regarding suspicious activity recently observed near that facility. I'm now told that the FBI has determined that the report lacks credibility. However, the Air Force is still investigating, and there have been similar reports from Davis-Monthan AFB, near Tucson, Arizona.
Davis-Monthan (or D-M as it's known in AF circles) is home to A-10 attack aircraft and EC-130H COMPASS CALL airborne jammers. It's also relatively close to our (relatively) unguarded southern border. There have been past concerns about a possible attack against a military installation in the southwestern U.S., so reports of suspicious activity near D-M (and other bases) can't be arbitrarily dismissed.