Around 400 sets of traffic lights in Johannesburg are out of order, after thieves stole the SIM cards they contained.
The SIM cards are used in conjunction with a GPS system so that the lights can alert the Johannesburg Road Agency (JRA) when they're faulty.
Since the cards were stolen, thousands of dollars' worth of bills have been run up, presumably in order to phone road signs and other long-lost relatives over the holiday period.
The JRA says the cards have now been cancelled. But, it says, they'll cost over a million dollars to replace.
"The JRA has been severely affected with this crime and this now means we have to fork out more money on something that we should not have spent a cent on," said spokesperson Thulani Makhubela.
There's a strong suspicion that it was an inside job, as only a third of traffic lights in the city contain SIM cards, and two-thirds of those were pinched. The location of the SIM-equipped lights was apprently known only to the JRA and the contractor who installed them.
"“We don’t know who is involved but we hope to get to the bottom of it,” said Makhubela.
It's not the first time the city's traffic lights have been targeted; late last year many disappeared altogther as thieves stole the metal poles for scrap.