Customs officers seized five puppies and five adult dogs at Dublin Port when they stopped two men disembarking a ferry from Holyhead on Tuesday morning.
The men, both Irish nationals in their 50s, were driving a van pulling a horsebox. A random check showed the men did not have pet passports for the animals.
The Pomeranian and Spaniel- type dogs and puppies are in the care of the DSPCA, who work in co-operation with other animal welfare organisations and Revenue to confront the illegal puppy trade.
Brian Gillen of the DSPCA said that while one of the animals is micro-chipped, it is not properly registered so he had "no clue" where the dogs came from. Since four of the dogs were adult females, he suspected they were for breeding.
He said it was “most unusual” to seize inbound dogs or puppies, since the majority of seizures are of animals leaving the country.
A follow-up investigation is now in progress.