South Africa had a wizard wheeze to make its traffic lights hi-tech by installing SIM cards inside them.

After all it was a brilliant idea to have your traffic lights communicate with each other and warn when they were faulty. According to the BBC the only problem is that the 400 lights are now all out of action after thieves stole the Sim cards and racked up thousands of dollars of calls on them.

The Johannesburg Road Agency (JRA) said it is investigating the possibility of an "inside job" after only the SIM card-fitted traffic lights were targeted. JRA believes a syndicate "with links on the inside" is behind the thefts. The thieves knew exactly which of the traffic lights had cards and no-one apart from JRA and its supplier knows which intersections have that system.

The thefts were "systematic and co-ordinated", a spokesman said. JRA has said it has blocked all the stolen SIM cards so that they cannot be used to make further calls.