The names, addresses and phone numbers of ‘millions’ of people have been stolen from a company which provides IT services to garages, broadcaster NOS reported on Thursday.

It is unclear exactly how the information was stolen, but the hacker offering the information for sale said the list ran to 7.3 million names, some of which appear more than once.

RDC, the IT company at the centre of the leak, said the figure is ‘realistic’. RDC offers garages an automated service to remind clients that it is time for their cars to have their annual APK check, using information that comes partly from the vehicle licensing authority RDW.

RDC, which has reported the theft to the privacy watchdog, said the information being offered for sale is old and may have been stolen a while ago. The company said it is unaware of any recent leak.

Nevertheless, McAfee IT security expert John Fokker told NOS the information is ‘super useful’ because the buyers will be able to see where expensive cars are located quickly and easily.

NOS said the seller had asked $35,000 for the information on a hackers’ forum at the weekend and had published some of the data online.

The NOS was able to access information about 58,000 people in Amsterdam with a car, and although the information about car ownership may be out of date, the broadcaster said other details such as addresses and emails may still be relevant.