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A small airplane plowed into the top of a flight safety center at an airport in Kansas after losing engine power on takeoff Thursday, killing at least four people, including the pilot, and injuring five others. Officials said they believe everyone in the building has been accounted for.

The Beechcraft King Air twin-engine plane reported trouble after taking off from Mid-Continent Airport in Wichita, about 9:50 a.m. (10:50 a.m. ET) and hit a two-story FlightSafety International building while trying to return to the runway, the Federal Aviation Administration said. The crash sent up thick plumes of black smoke that could be seen for miles.

The pilot, who was identified as Mark Goldstein, declared an emergency shortly after takeoff, telling the control tower, "We just lost the left engine," according to radio traffic recorded by LiveATC.net. Another person — it remained unclear whether it was an air traffic controller or the pilot of another aircraft — said a few minutes later: "Looks like you guys got a fire going on."

After a long stretch of silence, the tower reports, "We just lost the aircraft."

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Plane wheels are visible through the smoke at the scene of a small plane crash at an airport Thursday in Wichita, Kansas. Brian Youngers

One person was in serious condition at Via Christi Hospital St. Francis in Wichita, the hospital said. Four other people were treated and released.

Brian Youngers was in an office directly across the street, about 100 feet away, when the plane crashed.

"We heard a plane just buzz the top of the building and heard a big, huge crash — a bang. We immediately ran outside and across the street, and the building was already going up in flames. You could see part of the wing hanging off the building, burning, and the landing gear."

Youngers said he ran to the back side of the building to see whether he could help and saw workers streaming out. Soon after, an airport police officer arrived and asked him to move away from the scene.

Jaison Podkanowicz, who works near the airport, told NBC News he heard a noise that sounded like "something falling off a truck" and then saw the airplane "just sitting on the top of the building on fire" as "black, hazy smoke" billowed from a gaping hole.

Wichita Fire Chief Ron Blackwell said only the pilot was on the airplane. Valerie Wise, a spokeswoman for the airport, said about 100 people were in the FlightSafety building at the time of the crash.

Most of the building had been searched, but rescue crews could not get into one simulator room on the north end because of the danger that it could collapse. They were waiting for a structural engineer to advise them on the safest way to bring in heavy machinery.

FAA and National Transportation Safety Board investigators were at the scene Thursday. Senior NTSB Air Investigator Leah Yeager told reporters the initial investigation into the crash was at a standstill because the building had not been secured and cleared for entry by Wichita Fire Department officials. Yeager said NTSB investigators had possession of the plane's maintenance logs but had not reviewed them yet.

Firefighters try to put out a fire Thursday after a small plane crashed into a building at Mid-Continent Airport in Wichita, Kansas. Brian Corn / Zuma Press

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