The Federal Aviation Administration (FAA) issued a sudden Notice to Airmen (NOTAM) restricting flights over the southern border city of El Paso, Texas, for 10 days from Wednesday due to “special security reasons”.

The NOTAM did not specify what the special security reasons are. But El Paso is the headquarters for Fort Bliss, one of the major U.S. Army posts.

El Paso International Airport said in a statement that the NOTAM halts all flights heading to and leaving the airport, including commercial, cargo, and general aviation.

“Airport staff has reached out to the FAA, and we are pending additional guidance,” the statement said according to local media.

Chris Canales, an El Paso city representative, said in a post on his Reddit profile: “We’re all trying to work out why this crazy NOTAM was issued by the FAA.”

“Nobody local got advance notice — neither civilian nor military leadership,” Canales wrote.

Canales also noted the military “does not have carte blanche exemption” and that the “Army is fretting about their flights tomorrow just as much as everyone else.” 

Officials at El Paso International Airport have contacted the FAA and are awaiting additional information. Travelers have been told to contact their airlines for the information on flight status and rebooking options. 

The order applied to “NTL defense airspace” and warns that pilots who do not adhere to the order may be “intercepted, detained, and interviewed by law enforcement/security personnel.” 

The notice also warned that the U.S. government may use “deadly force” against any  aircraft deemed an “imminent security threat.” 

Local media have reported the “unexplained” notice closing airspace over El Paso and a large patch of southern New Mexico west of Santa Teresa. 

The publication El Paso Matters reported that the orders could cause massive disruption in the nation’s 23rd largest city. 

El Paso in West Texas has a population of more than 670,000 and is on the U.S.-Mexico border across from Ciudad Juarez. It hosts Fort Bliss, one of the largest U.S. Army installations in the country. 

The restricted area announced Tuesday also neighbors the military testing site in southern Mexico, White Sands Missile Range. 

This is a breaking news story. Updates to follow. 

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