Modern cars could be turned into lethal weapons by computer hackers working for enemy states or terrorists, experts have warned.
They say any car built since 2005 can be controlled remotely and many built between 2000 and 2005 are also vulnerable.
Government ministers in the UK have been urged to make laws forcing manufacturers to issue software updates.
Justin Cappos, a computer scientist at New York University, said: “Many of our enemies are nuclear powers but any nation with the ability to launch a cyber strike could kill millions of civilians by hacking cars. It’s daunting.”
“They can send messages to the brakes and shut off the power steering and lock people in the car.”
Hackers may already be causing accidents without authorities realizing as no one is looking for the evidence, he told The Times of London.
There are nine million Wi-Fi-connected cars on UK roads and each has up to 100 electronic control systems.
In 2015, researchers remotely took control of a 2014 Jeep Cherokee’s brakes, steering and transmission.
Carsten Maple, professor of cyber engineering at the University of Warwick, said: “We’ve already seen vehicles used as weapons. Cybersecurity researchers must ensure systems are engineered to stop new attacks.”
The Society of Motor Manufacturers and Traders said new cars were already being equipped with the “means to prevent remote hacking through regular software upgrades.”