-- Four people are dead after a prop plane crashed into a building this morning at an airport in Wichita, Kansas, officials said.
Five others have been rushed to a local hospital, fire marshal Brad Crisp said more than three hours after the crash.
"We don't know what may have caused the incident," Wichita Fire Department Chief Ron Blackwell said, noting that responders faced a "horrific firefight for several minutes."
The plane struck the top of the Flight Safety Building shortly before 10 a.m. and approximately 100 people were inside at the time, according to airport officials. The fatalities and injured were taken out of the building and the remaining individuals have all been accounted for.
Federal officials have confirmed that the incident is not related to terrorism.
Keith Rose, the CEO of Rose Aircraft Services Inc., which owned the plane, confirmed that the pilot was one of the two fatalities. He was the only person on board. The three other fatalities were all individuals in the building, which housed Cessna Citation Jet Simulators.
Rose said that the plane was headed to Mena, Arkansas, "for painting and interior refurbishing work."
Mid-Continent Airport officials reported on their Twitter feed that the building sustained serious damage with collapsed walls and ceilings. Smoke could be seen billowing from the building from miles away immediately after the crash.
Recently retired veteran air traffic controller Mark Goldstein died in the accident, according to the air traffic controllers association. The union and aviation sources confirmed to ABC News that he was the pilot of the plane that crashed.
Goldstein was an award-winning controller, twice garnering the top safety award for his region, union officials said. Goldstein was in the U.S. Navy and joined the FAA as a controller in 1987.
In a 2005 bio of Goldstein provided to ABC News, he is described as someone who has “an extensive background in aviation and is considered to be a conscientious controller.” And on a more personal note, Goldstein volunteered his time as a youth hockey coach.
Friend and fellow pilot Ron Ryan told ABC News that Goldstein was an expert pilot who had flown this particular plane many times. He was so well-known at this airport in fact that the air traffic controllers actually knew his voice and knew immediately it was he who was involved in today's accident based on his radio conversations with the tower, Ryan said.
Ryan said he would have trusted Goldstein "with his life."
ABC News' Matt Hosford contributed to this report.
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