POLICE have warned pet owners that they will not hesitate to smash windows if they see dogs suffering in the back of hot cars.

With temperatures on the rise, Camden Town police inspector Richard Berns tweeted a photograph of a destroyed back window and added: “We offer a free car ventilation service. All you have to do, is leave a dog locked in a hot car, we do the rest.”

Dogs suffering from heatstroke can be seen panting, looking confused or unsteady, vomiting or showing dark red gums and tongue. Some who get too hot can suffer seizures or fall into a coma.

Experts say some breeds are more susceptible including the Bulldog, French Bulldog, Greyhound, English Springer Spaniel, Cavalier King Charles Spaniel and the Staffordshire Bull Terrier.