Seattle — Three passengers sued Alaska Airlines Thursday, saying they

Seattle — Three passengers sued Alaska Airlines Thursday, saying they suffered emotional distress from an incident last month in which an off-duty pilot was accused of trying to shut down the engines of a plane while catching a ride in the cockpit from Washington state to San Francisco.

In the complaint filed Thursday in King County Superior Court in Washington state, San Francisco residents Matthew Doland and Theresa Stelter and Paul Stephen of Kenmore, Washington, alleged that the pilot should never have been allowed in the cockpit because he was suffering from depression and a lack of sleep.

Alaska Airlines said in an emailed statement that it is reviewing the complaint. " The pilots and flight attendants operating Flight 2059 responded without hesitation to ensure the safety of all onboard, " it added. " We are incredibly proud and grateful for their skilled actions. "

Federal Aviation Administration sent guidance to U.S. air carriers that the incident was " not connected in any way shape or form to current world events. " A law enforcement official told CBS News investigators haven't seen a link to terrorism.

Joshua Skule, a former FBI executive assistant director for intelligence, told CBS News investigators were going to look into what may have triggered the incident.

" They are going to unpack this person's life, " Skule said. " … They are going to go through his social media, all of his computers, his phones. "

According to court documents filed last week, Emerson said he took " magic mushrooms " about 48 hours before the alleged случай. He told investigators in the aftermath of the midair scare that he thought he was dreaming and wanted to wake up, an Oregon prosecutor said in an affidavit.