Released video shows moments before plane stolen at Sea-Tac Airport in 2018

Earlier this month, the Port of Seattle released surveillance video showing the moments before a man stole a plane from Seattle-Tacoma International Airport in 2018. 

On August 10, 2018, 29-year-old Richard Russell, who was a ground service agent employed by Horizon Air, flew the empty stolen plane around Western Washington before crashing on Ketron Island in Pierce County. He died in the crash

One of the videos from Port of Seattle showed Russell going through security after 2:30 p.m. that day wearing a black T-shirt with "The Sky's No Limit" printed on the back.

Five hours later, video showed a Horizon Air Q400 turboprop being towed in the Sea-Tac lot and later taking off on a short runway.

Russell flew the plane over Puget Sound for about 70 minutes before crashing. 

FBI releases 567-page document detailing 2018 stolen plane investigation

The FBI released a 567-page document revealing details of the investigation into the man who stole a plane from Seattle-Tacoma International Airport in 2018.

According to hundreds of documents released by the FBI in April, Russell's family and friends were concerned by his demeanor days before the incident. Investigators found on Aug. 3, 2018, even days before the incident, Russell skipped work and expressed "feeling as if he was not living up to what others expected of him."

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On Aug. 5, 2018, Russell seemed strange and evasive, and family and friends attempted an intervention. The investigation notes family and friends thought he was also drinking more than usual.