Washington, Oct 24 : An off-duty Alaska Airlines pilot was subdued as he attempted to shut down the engines on a flight while it was mid-air, authorities said. The Alaska Air Group said on Monday that the Horizon Air flight 2059 took off at 5.23 p.m. on Sunday from Everett, Washington, to San Francisco, California, reports Xinhua news agency. The flight, which had 80 passengers on board with two pilots flying and two flight attendants in the passenger cabin, diverted to Portland, Oregon, where it landed safely, and the Alaska Airlines pilot was arrested. The pilot, who was en route to San Francisco, where he was scheduled to be on a flight crew of a 737, sat in the jump seat on the flight deck just behind the captain and first officer flying the jet, local media reported. The Horizon Air captain and first officer "quickly responded", engine power was not lost, and the crew secured the aircraft without incident, said Alaska Air Group, the parent company of Alaska Airlines and its regional subsidiary Horizon Air. A Federal Aviation Administration notice called it a "significant security event". The "jump seat passenger" attempted "to disable aircraft engines while at cruise altitude by deploying the engine fire suppression system," the notice issued on Monday said. "The crew was able to subdue the suspect and was removed from the flight deck," it added. The engine fire suppression system on the Embraer 175 jet is activated by two handles on the instrument panel on the ceiling of the cockpit above the pilots. Pulling the handle cuts electrical and hydraulic power to the engine and closes the fuel line. Alaska Air spokesperson Alexa Rudin said that "fortunately some residual fuel remains in the line, and the quick reaction of our crew to reset the handles restored fuel flow and prevented fuel starvation". According to the Multnomah County Sheriff's Office website, the Alaska Airlines pilot, Joe Emerson, 44, was arrested by Port of Portland Police and booked into jail Monday morning. Emerson is being held on suspicion of attempted murder and reckless endangerment. /IANS