Dozens of motorists were left baffled after the keyfobs on their cars stopped working simultaneously.
Around 100 people who had parked outside a Tesco supermarket in Hertfordshire were left locked out of their vehicles and police are yet to discover why it happened.
In another strange twist, the incident is now being looked into by TV and radio regulator Ofcom.
Police do not believe that it's a case of foul play and have told people not to panic.
They said: "We have received a number of calls from members of the public who have not been able to access their vehicles in the car park of Tesco in Old North Road, Royston.
"For reasons yet unknown, there appears to be an issue in this area with key fobs not functioning correctly."