Government statistics agency CBS may have breached privacy rules by using T-Mobile mobile phone location data to track people’s movements, the NRC reported on Wednesday.

The NRC found that the CBS had used the data to establish how many people visited Amsterdam on King’s Day in 2018, and had on other occasions kept tabs on where people were during a number of hours in the day.

According to the CBS this was done in order to gain insights for policies in the areas of mobility, safety, disaster management and tourism, the paper said.

Privacy watchdog Autoriteit Persoonsgegevens AP told the NRC it was ‘remarkable’ that the CBS has effectively tracked and traced people by means of their phones when an emergency law is needed to allow the government to do the same for the coronavirus tracking app.

The government is planning to amend telecommunications legislation to allow phone data to be used for the app, a move which the privacy watchdog said earlier is essential.

The CBS said the examples cited by the paper were ‘pilot projects’ and anonymous, which it claims are not subject to the privacy rules. CBS workers who worked at the t-Mobile offices only had ‘limited access’ and, the agency said, it has not used data from T-Mobile for the last six months.