Tens of thousands of traffic lights are vulnerable to being hijacked by hackers – and the problem is not expected to be fixed until 2030.

An ethical hacker raised the alarm after hacking into the network that connects the emergency services to traffic lights so that the signals change to green when a response vehicle approaches with its blue lights on.

The hacker, 29-year-old Alwin Peppels, was able to change a light from red to green remotely, using a mechanism still in place in older traffic lights that work on short-range radio signals.

Newer types of traffic light are not susceptible to the hack because they work on different systems, but some of the older lights are not due to be replaced for another six years.

Peppels said he had worked on the device which mimics emergency service transmitters because he enjoys “digital puzzling”, but also to highlight the dangers of insecure infrastructure.

“Whether it’s criminal hackers or hostile countries that have targeted our infrastructure, it’s very important to ensure that these kinds of systems are properly protected,” he told RTL Nieuws.

“We need to be attentive and look at all the systems we use in our infrastructure.”

“This is a serious hack that can manipulate real-world objects,” cybersecurity expert Dave Maasland said “We used to think these kinds of things only happened in films, but as a society we are constantly running up against the fact that hacking our infrastructure is a reality.”