Although it is fine to buy items for your pooch online, such as dog chew toys and dog food, it is not a good idea to buy a dog from the internet.
The Labrador Lifeline Trust is urging prospective dog owners only to buy a pup from trusted expert organisations, reports bucksfreepress.co.uk.
Anne Carter, charity administrator, told the news provider: "We have instances of people coming to us having purchased a dog from one of these sites and then after a couple of days realising why it was sold in the first place and sadly, some of the cases are because of aggression to both humans and other dogs."
Jane Butler, area co-ordinator for the Association of Dog and Cat Homes, added that it is much better for everyone involved - both owners and sellers - that specialist breed organisations are used.
This is because breeders can be sure their dog is going to a suitable home, while buyers can be sure they are getting a healthy and safe pooch.