NORTHPORT, Ala. (AP) — Federal investigators say a pilot mismanaged his fuel supply, leading to “fuel starvation” of both engines of a plane that crashed in Alabama in 2016, killing all six people aboard.

The twin-engine Piper struck trees near the Tuscaloosa suburb of Northport as it attempted an emergency landing Aug. 14, 2016.

The National Transportation Safety Board says in a new report that it’s likely the pilot failed to switch the fuel selectors to tanks that contained fuel while in flight.

Authorities say the six people killed had taken off from Kissimmee, Florida, and were flying to Oxford, Mississippi, where they were from. They were identified as dentists Jason Farese and Lea Farese; dentist Michael Perry and his wife, Kim Perry, a nurse practitioner at the University of Mississippi; and dentist Austin Poole and his wife, Angie Poole.