Lie detectors added to airport security

Airline passengers will soon have to answer questions hooked up to a lie detector if they want to travel by plane, it has been revealed.

Domodedovo International Airport in Russia is to introduce the handheld polygraphs in July and every passenger will have to use one.

Passengers will be required to handover their bags and shoes for screening, and will not get them back until the lie detector test has been passed.

The machine asks four questions: the identity of the passenger; whether the passenger has ever lied to the authorities; whether they are carrying drugs; and whether they are carrying weapons.

"If a person fails to pass the test, he is accompanied by a special guard to a cubicle where he is asked questions in a more intense atmosphere," Vladimir Kornilov, IT director for the airport, told the Washington Post.

"We can understand that something like this could be uncomfortable for some passengers, but it is a necessary step."

The handheld lie detectors were developed by an Israeli firm and work by monitoring stress levels in the person's voice. The tests should take no longer than one minute.