Around 35 people were refused entry into Spain from Gibraltar yesterday, with more individuals reporting on social media that they have received the same treatment today.
Most of those refused entry were British nationals and holders of the blue and magenta Gibraltar Civilian Registration Cards.
The Borders and Coastguard Agency says a Gibraltarian was refused entry to Spain for failing to produce a Gibraltar red ID card.
A Ukrainian national resident in Gibraltar was also refused entry into Spain.
Most were asked for the reason of their visit to Spain and for flights or hotel bookings.
The Agency says it's not aware of any British national who presented their passport and a Gibraltar red ID card, and also asked to provide reasons for travel.
The Government says it understands that the existing status quo has not changed and that Gibraltar red ID card holders will not be required to stamp their passports when crossing the border to travel within Spain.