People are being urged not to unintentionally fuel a cruel puppy trade by buying one that's been smuggled into Kent.

The warning comes after nearly 100 puppies were seized in just a week during a covert operation at the UK border control as devious importers hone in on the Christmas trade.

Whilst many people's purchases may be well intended, unbeknown to them the internet has become a thriving marketplace for advertising illegally imported puppies and, in a sickening new trend, heavily pregnant dogs.

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The Dogs Trust says buying an illegally imported puppy could potentially families thousands of pounds in quarantine and vet bills, not to mention the emotional heartache if the puppy falls ill or worse, dies.

Adam Levy, rehoming centre regional manager at The Dogs Trust, said: "Unfortunately Kent really is the main gateway for bringing these pups across.

"So whether it's via Eurotunnel and Folkestone or the ferries at Dover they are bringing them across underage with falsified passports, and quite often just smuggling them in the backs of cars just because they can get such high amounts for them in the UK."

Only half (48%) of respondents the Dogs Trust surveyed said they would be concerned if their most recently bought puppy was imported illegally and a third (33%) said they would buy a dog from an online classified site or social media – highlighting the scale of the problem.

The results prompted the charity to release some facts about the illegal puppy trade following a recent investigation.

• Puppies as young as four weeks were transported barely weaned during a cramped 1,000 mile, 30-hour journey across Europe
• The animals were observed vomiting and another eating their own faeces during a journey from Lithuania with no air conditioning, and outside temperatures of 25C
• A vet in Lithuania was selling sedatives to allow puppies to be smuggled across the British border
• Vets in Poland and Lithuania were filmed falsifying pet passports and faking rabies vaccination records, enabling underage puppies to slip through the net without the correct paperwork
• In 2016, 275,876 dogs travelled to Great Britain, more than treble the number recorded in2011
• Many of the puppies were significantly younger than 15 weeks to appear cuter to buyers

The charity has produced some advice to help people make sensible choices and avoid being tricked into buying puppies which have been illegally imported from Europe.

It says buyers should ask to see mum and pup together, get all the puppy's paperwork before going home, take their puppy to a vet for a health check, report suspicious sellers or breeders, and walk away if you are unsure.

The trust also advises people not to meet anywhere that is not the puppy's home, buy from anyone who can supply various breeds on demand, buy a puppy that looks too young/small or underweight, or allow yourself to be pressured into a sale.