Facial recognition software that spots when someone is lying could help weed out terrorists and drug smugglers at airports.

After analysing millions of frames of footage, researchers have discovered the giveaway facial expressions of untrustworthy individuals that could be utilised by smart surveillance cameras to assess boarding passengers.

The artificial intelligence would aid officers decide whether a suspicious person in an immigration queue is telling the truth or just nervous. It could also minimise cases of racial profiling by airport staff.