GLENDALE, Ariz. (AP) — The pilots flying an F-16 fighter jet that went down near Luke Air Force Base in suburban Phoenix reported hitting a bird shortly after takeoff, the Air Force general who commands their base said Thursday.

The two pilots, who were practicing landings and takeoffs at the base Wednesday evening, ejected safely and the fighter crashed in a farm field near the base.

"Shortly before the accident the pilot reported a bird strike," Brig. Gen. Mike Rothstein told reporters at the base 15 miles west of Phoenix.

The plane had just taken off when the pilots reported hitting a bird and the engine in the plane malfunctioned, 56th Operations Group commander Col. John Hanna said. They had little time to react.

"It sounds like they did a good job, the airplane didn't hit anybody or anything and they both survived with what I know is no injuries," Hanna told The Associated Press. "It's about as good as it gets when you have any kind of accident where you destroy an airplane."

Base spokeswoman Lt. Candice Dillitte said there's nothing to indicate a fleet-wide problem with the jets, but the Air Force will investigate the cause. The Air Force has more than 1,000 of the single-engine fighters.

The base, 15 miles west of Phoenix in Glendale, is the world's largest F-16 pilot training base and had 138 F-16s before Wednesday's crash. An instructor and a student were flying the jet that crashed.

The base is getting ready to transition to the military's new F-35 fighter. The Air Force announced Thursday it would receive three additional squadrons, bringing the total to 144 within about 10 years. The first plane is set to arrive next spring.

Witnesses said they heard the jet's engine sputtering and popping just before the plane went down. Photos posted on Twitter showed civilians helping two male pilots alongside a freshly plowed field.

Rothstein said the fact that the jet came down in farmland wasn't an accident. Glendale and other nearly cities have worked with the state to maintain open space around the base despite the rapid urbanization of the area.

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Any engine problem shortly after takeoff is extremely dangerous and the pilots needed to react quickly, Hanna said.

"Certainly low altitude ejections are some of the more harrowing things that can happen, because you're close to the ground and a lot of things have to happen in a hurry in order for all of the ejection process to occur successfully," Hanna said. "You end up on the ground, able to stand, gather your gear and walk to the nearest pickup truck that's got some water sitting in it. So this worked out pretty well."

Bird strikes can severely damage jet engines. US Airways Flight 1549 lost both engines shortly after takeoff from LaGuardia Airport after hitting birds in January 2009 but landed safely on the Hudson River.

An inspector general's audit last year criticized the Federal Aviation Administration for not doing enough to stop bird strikes. The report cited a five-fold increase in bird strikes over the last two decades, from 1,770 reported in 1990 to 9,840 reported in 2011, due in part to growing bird populations. The strikes have led to at least 24 deaths and 235 injuries in the United States since 1988.