A chihuahua being walked by a 14-year-old boy has been brutally mauled to death on Hampstead Heath.

The pet pooch was scooped up by the teenager when a bull mastiff, off its lead, approached the tiny dog in Limes Avenue off East Heath Road in South End Green. The spooked chihuahua wriggled free, but was caught in midair in the jaws of the larger mutt which savaged the little canine at around 3pm on July 7.

The chihuahua died at the scene and the mastiff was muzzled and taken home by its owner who was called to the scene and interviewed by police.

Both dogs were being walked by their owners’ friends.

A police source said: “When you have a bull mastiff and a chihuahua squaring up to each other the odds start to stack up against the smaller dog.

“The chihuahua jumped straight into the mastiff and dogs do what they will do to kill their prey.”

The Heath Constabulary are investigating and the owner of the bull mastiff could face a criminal prosecution under a Heath byelaw.

The Manager of the Heath Constabulary Richard Gentry said: “Hampstead Heath welcomes responsible dog owners and dog walkers. This recent incident demonstrates that there are a minority of dog owners and walkers who have a lack of control over their dog and this has led to a tragic outcome where someone’s beloved pet has been killed.”