PORTLAND, Ore. (KOIN) – An Alaska Airlines plane made an emergency landing at Portland International Airport on Sunday after a “credible threat to an authorized occupant” on board — and now the suspect, identified as an off-duty pilot, is facing 167 charges.

Officials with the Port of Portland identified the suspect as 44-year-old Joseph D. Emerson, who was taken into custody after Flight 2059 was diverted to PDX.

The airline said in a statement that no weapons were involved.

Emerson faces 83 counts of first-degree attempted murder, 83 counts of reckless endangerment and one count of endangering an aircraft.

According to Alaska Airlines, the flight — on a Horizon Air passenger jet — was headed from Everett, Washington, to San Francisco. Alaska Airlines owns Horizon, a regional carrier.

Alaska Airlines said an off-duty pilot, later identified as Emerson, who was sitting in the jump seat, caused a disturbance in the cockpit of the plane and “attempted to disrupt the operation of the engines.”

The crew managed to secure the plane, and Alaska Airlines said they worked with air traffic control to divert the flight to PDX.

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 LiveATC.com. “Other than that, we want law enforcement as soon as we get on the ground and parked.”

The FBI office in Portland said it was investigating “and can assure the traveling public there is no continuing threat related to this incident.”

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

Officials confirmed the suspect was taken into custody after the plane landed, and the plane’s passengers were all able to board a later flight.

According to FAA records, Emerson holds a license to fly airline planes. It was not immediately certain which airline he works for.

The 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.

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.

The Associated Press contributed to this report.