MPs have called for answers on reports that the tax office illegally collected information about dual nationals and used it when investigating child benefit abuses.

RTL Nieuws and Trouw said on Monday morning that the Dutch privacy watchdog Autoriteit Persoonsgegevens is investigating claims the tax office decided who would be investigated for potential fraud and lose their benefits on the basis of their ethnic profile.

The investigation was started after a daycare centre in Almere and childminding agency in Eindhoven reported their concerns to the AP. The agency had noted that a tax office worker was keeping records about dual national parents, while the daycare centre realised half its parents lost their subsidy, almost all of whom had foreign backgrounds.

The AP told the paper and website that it collecting information about race and ethnicity is ‘almost always’ banned, and pointed out that nationality is no longer included in the national residency register either.

The tax office has denied using nationality as a basis for deciding to investigate fraud.

In 2014, 230 families were left in serious financial trouble after the tax office stopped their child benefits overnight because of ‘indications of fraud’. The were also forced to pay back the cash.

Last year, officials admitted that fraud was involved in just 27 cases.