Officers arrested the couple on the island of Majorca, where they are suspected of raising desert lynxes and servals, a wild cat native to Africa, as well as hybrid species created by crossing these breeds with domestic cats, police said in a statement.

Further investigations found that their activities were just "the tip of the iceberg" of an international trafficking operation of protected species such as white tigers and black panthers "involving breeders, transporters and veterinarians", they said.

"Most of the animals offered for sale came from countries such as Russia, Belarus and Ukraine to be smuggled into the European Union," they added.

Police suspect the animals were brought into the European Union via Poland from Belarus, and were then offered across the bloc with false documentation.

Among the other species the couple offered for sale on its social media accounts were European lynxes, hyenas and pumas.

Police said the suspects had offered a clouded leopard, one of the world's most rare and elusive cats, at a price of 60,000 euros ($68,000).

Officers also seized a caracal, a desert lynx known for its distinctive long ear tufts, as well as two servals and 16 hybrid felines.

They also seized more than 40 animal passports from Russia, Belarus and China as part of the operation.