Flight diverted to Portland over 'credible security threat,' off-duty pilot charged with 83 attempted murders

A flight that took off from Washington state bound for San Francisco was diverted to Portland, Oregon, over a "credible security threat" Sunday, airline officials confirmed to Fox News Digital.

A man, identified as an off-duty Alaska Airlines pilot, has since been arrested and charged with more than 80 counts of attempted murder after he tried to disable the plane's engines while the plane was airborne, the Seattle Times reported.

"Alaska Airlines Flight 2059 operated by Horizon Air from Everett, WA (PAE) to San Francisco, CA (SFO) reported a credible security threat related to an authorized occupant in the flight deck jump seat. The crew secured the aircraft without incident," Alaska Airlines said in a statement to Fox News Digital on Monday.

"Following appropriate FAA procedures and guidance from air traffic control, the flight safely diverted to Portland International Airport. The event is being investigated by law enforcement authorities," the airline added. "All passengers on board were able to travel on a later flight. 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."

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The FBI confirmed it is investigating.

"One man is under arrest on state charges in Oregon, booked by the Port of Portland Police Department, after an incident in the air on Horizon Air flight 2059 from Everett, WA to San Francisco, CA," the FBI's Portland's field office said in a statement obtained by Fox News Digital. "The airplane's pilot was able to safely land the plane at Portland International Airport around 6:25 pm on Sunday, October 22. No injuries were reported. The FBI is investigating and can assure the traveling public there is no continuing threat related to this incident."

A senior law enforcement source confirmed to Fox News there's no relation to terrorism at this point in the investigation.

The Federal Aviation Administration directed Fox News Digital to reach out to local law enforcement agencies for more information. Online jail records show Joseph David Emerson, 44, was arrested by the Port of Portland and booked into Multnomah County Jail shortly after 4 a.m. Monday on 167 counts, including 83 counts of attempted murder, 83 counts of reckless endangerment and one count of endangering an aircraft.

According to a memo seen by Fox News Digital, American Airlines pilots were warned Monday to "maintain vigilance and heightened situational awareness."

According to the Seattle Times, the man ultimately charged in the incident had been sitting in the jumper seat on the flight deck just behind the captain and first officer of the Embraer E-175 regional jet; it is custom for airline employees to hitch a free ride back to their home base if a seat is available and sometimes chat with the pilot and flight crew during their ride.

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The working pilot told Portland air traffic controllers, "We’ve got the guy that tried to shut the engines down out of the cockpit," according to audio of the exchange shared on the LiveATC website.

"It doesn’t seem like he’s causing any issue at the back. I think he’s subdued," the flying pilot added. "Other than that, we want law enforcement as soon as we get on the ground and parked."

Fox News Digital also reached out to the Multnomah County Sheriff's Office for comment Monday.

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Journalist Jon Ostrower wrote on X, formerly Twitter, that the FAA sent a broader security notice to U.S. carriers, according to a U.S. airline staffer who received the message directly.

"Last night a significant security event occurred on a US Air Carrier involving a validated jump seat passenger attempting to disable aircraft engines while at cruise altitude by deploying the engine fire suppression system," the notice said, according to Ostrower. "The crew was able to subdue the suspect and was removed from the flight deck. The flight diverted and landed safely."

"The event remains under investigation by law enforcement, no further details will be provided at this time," the FAA reportedly added.

This is a developing story. Check back for updates.