The twin-engine plane crashed at the end of a runway at the airport near Ben Durrance Road.
A Polk County Fire Rescue spokesperson said four people were killed in the crash.
Emergency operators received a call about the crash at 7:20 a.m.
The Bartow Municipal Airport is the former location of a U.S. Air Force Base and is also referred to as the Bartow Air Base. It is located just off of US 17 near Spirit Lake Road.
Investigators with the NTSB and FAA are headed to the crash scene.
Details about what caused the crash have not been released.
WFLA Storm Team Meteorologist Ed Bloodsworth said around the time of the crash, weather data at the airport was reporting zero visibility of less than 300 feet because of the fog. The weather data is from the Automated Surface Observing System (ASOS) which is located at the airport. The Tampa Bay area is under a dense fog advisory until 10 a.m.
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