The FBI and National Transportation Safety Board continue to investigate the stolen plane incident at Sea-Tac Airport.

A further examination of audio posted from tower tapes from LIVEATC.Net recorded a pilot from another airline telling air traffic controllers about the Horizon Q400 turboprop cutting ahead of a Delta jet taxiing for takeoff.

β€œHe came flying out of the cargo area in front of Delta,” said the pilot in a hard-to-hear portion of the recording.

Air Traffic Controller: "Which cargo area, one or two?”

Pilot: "The one further to the north."

The northernmost cargo area is known to be where the Horizon plane had been parked for the night.

An airport spokesman says this was not a close call. It is not publicly known yet how far apart the two planes were.

As Horizon worker Richard Russell took the plane airborne, the air traffic controller is heard becoming more insistent that Russell identify himself.

RELATED: Air traffic controller praised for efforts to help Seattle plane thief

In a preliminary report of the incident, the NTSB confirmed no flight plan was filed. The FBI is the lead agency in the investigation, which is not considered an accident β€” but a crime. The NTSB is providing a supporting role.

COMPLETE COVERAGE OF STOLEN PLANE

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