An off-duty pilot riding in the cockpit of an Alaska Airlines flight from Washington state to San Francisco on Sunday has been arrested and is now facing dozens of attempted murder charges for allegedly trying to shut down the plane's engines mid-flight, authorities have confirmed.

The suspect has been identified as Alaska Airlines pilot Joseph D. Emerson, 44. Alaska Airlines stated that Emerson attempted to cut off fuel to the engines, but the quick response of the aircraft's captain and first officer prevented the engines from failing completely. The flight crew managed to subdue Emerson.

The incident occurred on Alaska Airlines Flight 2059, operated by regional carrier Horizon Air, shortly after taking off from Everett, Washington. The airline reported a "security threat related to an off-duty Alaskan Airlines pilot, identified as Captain Joseph Emerson, who was traveling in the flight deck jump seat."

According to the airline, while in the cockpit, Emerson attempted to shut down both engines by pulling the fire extinguisher handles. However, the crew's swift actions allowed them to reset the handles and restore the flow of fuel, avoiding engine failure.

The flight was forced to divert to Portland, Oregon, where Emerson was taken into custody by Port of Portland police. He is currently being held without bail at the Multnomah County Jail. Emerson faces 83 felony counts of attempted murder, 83 counts of reckless endangerment, and one count of endangering an aircraft. He is expected to appear in court on Tuesday afternoon.

Investigative sources have revealed that authorities do not suspect terrorism or ideologically motivated violence. Instead, they believe the incident may have resulted from a mental health episode. As a result, officials are preparing to order a psychological assessment of Emerson as part of the court proceedings.

Passengers on the flight recounted their experiences, describing the calmness maintained by the airline crew throughout the incident. The FBI confirmed that no injuries were reported, and all passengers were able to reach San Francisco with a new crew and aircraft.

The FBI, along with the Port of Portland police, is currently investigating the incident. The Federal Aviation Administration is providing support to local law enforcement in their efforts.

Emerson, who has been in the aviation industry for at least two decades, began his career with Alaska Air Group in 2001 as a first officer with Horizon. He later joined Virgin America as a pilot and became a first officer with Alaska Airlines after the acquisition of Virgin America in 2016. During his career, Emerson maintained all necessary FAA certifications for flying multiple aircraft types.

The investigation is ongoing, and it is possible that Emerson may face additional federal charges in connection with the incident.