The apparent theft on November 1 of a Piper PA-25 Pawnee cropduster near Mexicali, Mexico, was the subject of a Transportation Security Administration advisory notice. “Although there is currently no indication that this has any connection to terrorist activity, the theft is cause for concern,” said last month’s notice. “Past information indicates that members of al-Qaeda may have planned–or may still be planning–to disperse biological or chemical agents from cropdusting aircraft.” The stolen Mexican-registered Pawnee was still unaccounted for at press time.