(NewsNation) — An off-duty pilot is being charged with more than 83 counts of attempted murder after allegedly attempting to bring down an Alaska Airlines flight to San Francisco on Sunday.

Alaska Airlines pilot Joseph Emerson was riding in the cockpit’s jump seat as he flew from Washington to San Francisco, where he was set to fly another plane. It’s not uncommon for crew members flying for work to travel in jump seats on the flight deck. You can read more about what NewsNation knows about the alleged suspect here.

According to a statement from the airline, the pilot for Flight 2059 reported a credible security threat after Emerson attempted to disrupt the operation of the engines.

“The Horizon Captain and First Officer quickly responded, engine power was not lost and the crew secured the aircraft without incident,” the airline said.

An FAA alert said Emerson attempted to disrupt the operation of engines while the plane was at cruising altitude by activating the engine’s fire suppression systems. The Horizon flight, operated by Alaska Airlines, was carrying 80 passengers and four crew members.

The flight crew subdued Emerson and handcuffed him to a seat for the duration of the flight as the plane was diverted to Portland. He was arrested on landing.

In a statement, the FAA said it is actively investigating the incident.

“The FAA is engaged with Alaska and Horizon airlines and is supporting law enforcement investigations into Sunday evening’s incident aboard a Horizon Air flight. Please contact law enforcement for further details,” the agency said.

Emerson is facing 83 charges for first-degree attempted murder, 83 charges of reckless endangerment and one charge of endangering an aircraft.

The FAA sent a notice Monday morning advising flight crews to be vigilant but saying the incident
“is not connected in any way shape or form to current world events.”