More dogs were reported stolen in London last year, figures reveal.
A missing pets charity said an increase in dog thefts nationally is linked to the coronavirus pandemic, and warned new owners might accidentally be buying stolen dogs.
The Met Police recorded 422 dog thefts in 2021, according to a Freedom of Information request from Direct Line Pet Insurance.
This was up from 318 in 2020, and the highest number since the company's records began in 2015.
Across the UK, 2,077 dogs were reported stolen to 35 police forces which responded to the FOI request – though Direct Line Pet Insurance estimates the real figure to be as high as 2,760.
This estimate was up from 2,438 in 2020 and the highest number since their records began in 2015.
Madeline Pike, veterinary nurse for Direct Line Pet Insurance, said: “It’s devastating to see the number of dogs stolen continue to increase across the country.
"Unfortunately, the increase in dog ownership since the pandemic began and the subsequent rise in prices of these animals seems to make the crime even more appealing to thieves."
She said dog owners should take precautions such as keeping their pets on a lead when in busy areas, and avoiding leaving a dog tied up outside a shop, or left inside an empty car.
Dyfed and Powys saw the highest rate of stolen canines last year, with 36 incidents per 100,000 households.
Meanwhile, Surrey had a rate of just two dog thefts per 100,000 households.
In London, the rate was 12.
Along with an increase in thefts across the UK, the proportion of pooches returned to their owners also rose last year, to 22%.
Norfolk Constabulary reunited the greatest proportion of dogs with owners, returning 25 out of 29.
By comparison, none of the 10 dogs taken in Lincolnshire were returned.
The Stolen and Missing Pets Alliance said the demand for dogs during lockdown caused a "huge spike" in them being stolen for breeding, with their value also increasing.
Debbie Matthews, chief executive of the charity, said: "Dogs were also essentially being stolen ‘to order’ for people who were looking for a certain breed, but would never know that they were receiving a stolen dog.
"We would always recommend that a new owner gets the pet’s microchip registration checked as soon as possible."
Direct Line Pet Insurance said French bulldogs were the most stolen breed in 2021, followed by Jack Russells, chihuahuas and pugs.
The National Police Chiefs’ Council said those buying a dog should seek advice online first, check where it has come from, and ensure that it is being bought legally.
Deputy Chief Constable Amanda Blakeman, NPCC lead for acquisitive crime, added: "This helps reduce the ability of criminals to operate in this market.
"We would remind the public that rescue centres can often be a reliable and trusted source for those wishing to offer a home to a pet."