A State Department spokeswoman says a man who ranted about national security and repeatedly screamed "I'm dead" during a flight from Hong Kong to New Jersey once worked at the agency.
The spokeswoman said Tuesday in Washington that the passenger ended his time at the department in 2006. She gave no details about his job or why he no longer works for the agency.
The man started screaming nine hours into Monday's 15-hour flight to Newark Liberty Airport. At one point, a passenger says, the man claimed people were trying to poison him.
In a recording of part of his rant, he can be heard saying "your life is in jeopardy," and talking about the CIA and NSA.
Passengers helped subdue him.
"He started reaching for something in his jacket, and so a few of us jumped on him, basically, put him to the floor, at the same time the crew brought plastic handcuffs and we were able to restrain him," said passenger Jacques Roizen.
Passengers say the man was clearly not stable. The FBI says he was hospitalized after being taken off the plane.
It was not clear whether he would face charges.