Dogs Trust is appealing for information after a Maltese cross that was in its care was stolen.
The four-year-old dog, Denny, was being walked by a member of the public who was interested in rehoming him.
However, the two then disappeared from the Ballymena centre and staff are now concerned about the dog’s welfare.
Marey Carney, centre manager, said: "The staff are very upset that such an incident has happened and hope that is was simply a lack of understanding on the gentleman’s behalf.
"He is a very friendly dog and has only been with us for just over a week, however in this time he has become a big hit with the staff."
She added that the charity’s priority is the dog’s welfare and that they are hoping anyone with information will contact them on 028 2565 2977.
The police have been contacted, but, at present they are unable to help with the search.