Off-duty pilot Joseph Emerson accused of trying to shut off engines on flight from Everett to San Francisco

An Alaska Airlines flight on its way to San Francisco from Everett's Paine Field was diverted to Portland on Sunday after officials said an off-duty pilot tried to shut the plane's engine.   

The Seattle-based airline company said in a statement that Flight 2059, operated by Horizon Air, reported a credible security threat related to the off-duty Alaska Airlines pilot, who was traveling in the flight deck jump seat. 

According to the airline company, the pilot tried to "disrupt the operation of the engines."

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The Horizon Captain and First officer quickly responded and crews secured the plane without incident. Engine power was not lost. 

One of the pilots told air traffic controllers that the man who posed the threat had been removed from the cockpit.

"We’ve got the guy that tried to shut the engines down out of the cockpit. And he — doesn’t sound like he’s causing any issue in the back right now, and I think he’s subdued," one of the pilots said on audio captured by "Other than that, we want law enforcement as soon as we get on the ground and parked."

After the plane was diverted to Portland International Airport, the off-duty pilot was taken into custody.

Authorities in Oregon identified the man as Joseph David Emerson, 44. He was being held Monday on 83 counts each of attempted murder and reckless endangerment and one count of endangering an aircraft, according to the Multnomah County Sheriff’s Office.

All passengers on board were able to book a later flight to San Francisco.

The near disaster evokes some of the same security concerns surrounding Richard Russel, the 29-year-old Horizon ground crew employee who managed to fly off with a Q400 passenger plane in Aug. 2018. Over the next 70 minutes, Russell flew from the Cascades to the Olympics, over scores of houses and several communities, and did stunts in mid-air

Fearing the worst, two military jets were scrambled, but Russell eventually crashed the plane on Ketron island in Pierce County killing himself.

FBI documents released last year suggested Russel was struggling with mental health issues leading up to the crash.

"We are grateful for the professional handling of the situation by the Horizon flight crew and appreciate our guests’ calm and patience throughout this event," Alaska Airlines said.

The incident is being investigated by authorities, including the FBI and the Port of Portland Police Department.

The Federal Aviation Administration said it was helping law enforcement investigations, but declined further comment about the incident.

FAA records indicate that Emerson has a valid license to fly airline planes. It was not clear Monday whether he was represented by a lawyer.

When the jump seat, a third seat in the cockpit, is occupied it’s often filled by an off-duty pilot, but the seat can be used by other airline employees or federal safety inspectors.

Sunday's incident occurred on a 76-seat Horizon Air Embraer 175 that left Everett, Washington, at 5:23 p.m. local time and landed in Portland an hour later. Alaska Airlines did not immediately say how many passengers were on board.

The Associated Press contributed to this report.