Families are being urged not to buy puppies online this Christmas amid fears the money exchanged could be laundered by criminal gangs to support drug traffickers and other illegal activities.
The warning comes after illegally-bred puppies sold through black-market trade on social media and via small advert sites were identified by prosecutors as a "significant source of revenue for serious organised crime gangs".
The market in Scotland last year was estimated to be worth £13m.
The Crown Office and Procurator Fiscal Service (COPFS) has issued a stark warning to all those tempted into buying a puppy online from unlicensed sellers - where some designer breeds can fetch as much as £3,000.
Kenny Donnelly, deputy crown agent for specialist casework, said unscrupulous breeders are "operating online and targeting unsuspecting members of the public".
He added: "We are aware that organised crime gangs have infiltrated this activity and continue to use the huge profits they accrue from it to inflict widespread harm on communities throughout Scotland.
"Illegal puppy farming has grown significantly among serious organised crime gangs as a way of raising finance. It plays a part in financing crime in Scotland. These gangs are involved in the distribution of illegal drugs and money laundering.
"Therefore, it is critically important that anyone considering buying a puppy is aware of the pitfalls in respect of not buying from legitimate dog breeders and unintentionally supporting this cruel and illegal trade which exploits pets and causes them terrible suffering."
Mr Donnelly said the trade is "inevitably more focused at Christmas", so would "seriously urge" people to only buy from licensed breeders.
He added: "By doing this, you are also helping to choke off a revenue supply to serious organised crime gangs and reducing the harm they inflict on Scottish communities."
So far this year, the Scottish SPCA has received 336 calls in connection with suspected puppy farms and puppy breeding.
The animal welfare charity said many pets later suffer severe health problems and either cost their owners huge vets' bills or are too ill to survive their first few months.
Mike Flynn, Scottish SPCA chief superintendent, said: "Although the low-welfare trade in puppies has slowed due to the ending of lockdown and the cost of living crisis, we know that unscrupulous breeders are still out there targeting unsuspecting members of the public.
"Trafficked pups often look fine when they are purchased, but problems will begin to show at a later stage.
"Our message to the general public remains the same - do not buy online or from someone where it is impossible to verify where the dog is actually coming from. The only way this will disappear, and people stop profiteering at the expense of these dogs, is if public demand stops."