A US domestic flight made an emergency landing after the captain began yelling about a bomb, passengers say.
The airline said a "medical situation" involving the flight captain prompted the landing in Amarillo, Texas, about three-and-a-half hours into the flight, the BBC reports.
JetBlue flight 191 from New York to Las Vegas was carrying 135 passengers when a crew member had to be locked out of the cockpit and restrained.
Local police and the FBI are said to be investigating the incident.
JetBlue has said the pilot in charge of the plane decided to land at about 10:00 am Wednesday.
The flight touched down in Amarillo 10 minutes later, JetBlue said in a statement, and a new aircraft later arrived to take passengers on to Las Vegas.
Passengers recalled the confused scenes on board and said the captain had begun shouting about Afghanistan and al-Qaeda.
On arrival in Las Vegas one passenger, David Gonzales, told US network ABC that he had grabbed the captain and put him in a headlock in an attempt to subdue him.