CHALDOVAR, Kyrgyzstan — An aerial tanker jet reportedly flown by a Fairchild Air Force Base crew crashed today in the rugged mountains of Kyrgyzstan, the Central Asian nation where the U.S. operates an air base key to the war in Afghanistan.

A spokesman for U.S. Rep. C.W. Bill Young, R-Florida, told Reuters News Service that the congressman was advised the KC-135 Stratotanker was based out of McConnell Air Force Base in Kansas but that it was being operated by a Fairchild crew. Fairchild Air Force Base officials would not confirm the report today.

Master Sgt. Eugene Taylor at Fairchild, located west of Spokane, acknowledged being aware of those news accounts but said he could not confirm them.

“Until the Air Force notifies the next of kin, the Air Force will not confirm where the crew was from or the aircraft,” Taylor said. “It’s just the process the Air Force has enacted to protect the personnel and their families.”

Because of the nature of the crash, the official notification could take some time, Taylor explained.

“Right now the crew is officially listed as missing because we don’t have any bodies. The airplane blew up in flight,” he said. “Because they are listed as missing, that might hold up the notification process.”

There was no immediate word on whether any of the crew members were able to eject, and if they had the search for survivors would be complicated by the harsh terrain in the region.

The U.S. base in Kyrgyzstan, called the Transit Center at Manas, said it had no immediate information on the cause of the crash, but a resident of the agricultural and sheep-grazing area said the plane exploded in flight.

“I was working with my father in the field, and I heard an explosion. When I looked up at the sky I saw the fire. When it was falling, the plane split into three pieces,” Sherikbek Turusbekov said.

The crash site is near Chaldovar, a village about 100 miles (160 kilometers) west of the base. Pieces of the plane, including its tail, lay in a grassy field bordered by mountains; the air was infused with the heavy stench of petrol.

The base, which is adjacent to the Manas International Airport outside the Kyrgyz capital of Bishkek, was established in late 2001 to support the international military campaign in Afghanistan. It functions as an interim point for troops going into or out of Afghanistan and as a home for the tanker planes that refuel warplanes in flight.

The base has been the subject of a contentious dispute between the United States and its host nation.

In 2009, the U.S. reached an agreement with the Kyrgyz government to use it in return for $60 million a year. But the lease runs out in June 2014, and the U.S. wants to keep it longer to aid in the withdrawal of troops from Afghanistan. Kyrgyzstan is reluctant to extend the lease.

On Monday, a Boeing 747 cargo plane crashed just after takeoff from the U.S. military base in Bagram, Afghanistan, killing all seven people aboard.