Jewish ritual sparks in-flight lockdown

Pilots on an Alaska Airlines flight from Mexico City to Los Angeles locked down the cockpit and alerted authorities on Sunday when flight crew grew alarmed at the behaviour of three men who turned out to be conducting an elaborate Orthodox Jewish prayer ritual.

The men, all Mexican nationals, began the ritual, known as tefillin, which involves tying leather straps and small wooden boxes to the body, and the crew of Flight 241 alerted the cockpit, airline spokeswoman Bobbie Egan said.

"Shortly after take-off, a flight attendant saw what she believed was unusual behaviour from three passengers on board," Ms Egan said in a statement. "The three passengers were praying aloud in Hebrew and were wearing what appeared to be leather straps on their foreheads and arms."

The cockpit was placed on a security lockdown for the rest of the flight – meaning the door could not be opened, even by pilots.

Normal protocol calls for the cockpit to be locked, but on longer flights the pilots will leave and return to the flight deck.

The FBI, customs agents, police and a full assignment of fire trucks met the plane at the gate at Los Angeles International Airport, and the men were escorted off.

After questioning by the FBI, the men were released.