The Transportation Security Administration on Thursday issued an advisory urging private jet owners and general aviation airports to review security measures after a message was posted in Arabic on a Web forum on April 13 urging all Muslims to destroy American business jets “usually used by distinguished (people) and businessmen.” The message advised how to identify U.S. aircraft and provided the tail number of a private aircraft allegedly used by the CIA. With the European Business Aviation Convention & Exhibition set to open next week, NBAA said it is taking the threat “pretty seriously.” In addition, Gulfstream on Friday sent a maintenance and operations letter to all its customers saying, “Gulfstream has not received any direct threats; however it is important that Gulfstream operators review the [TSA advisory] information.”