People living in the Republic of Ireland have been warned to stop booking Covid-19 vaccination jabs at centres north of the border unless they are registered with a doctor there or have or have an NHS number.
Hundreds of people from south of the border, some travelling from as far as Dublin and Galway, have been turned away from centres across Northern Ireland in recent days.
The online vaccination booking system does not require applicants to give their home address or medical card number to book a slot, but those details must be provided on arrival, as well as photographic ID.
Some recent media reports suggested that anyone living in the Republic of Ireland can book jabs across the border, but that is not the case.