A lost dog has been reunited with her family after navigating a motorway and railway lines during a perilous midnight 15-mile journey home.

Bella, two, a jack russell cross terrier from Merton Park, disappeared into the brushes by Pembroke Lodge, Richmond Park during a run on Sunday morning.

Owner Stephen Sinnott searched desperately for the dog with jogging partner Darryl McDonald for half an hour before calling home to ask his wife, Barbara, to bring the car.

The search continued throughout the afternoon but to no avail, and despondent, the worried group were forced to return home and break the news to the Sinnott family's three young children.

Mr Sinnott, a quantity surveyor who lives on Mostyn Road, said: "Both of us were afraid she might have run down a fox hole and couldn't get out."

Daughter Sian Sinnott could not stop crying for Bella to return home.

Then, at 4.30am, the family woke to sounds of scratching at the front door and were astonished to find their lost pet waiting to be let in.

She had made the 15-mile journey home successfully navigating the A3 and rail lines that stood between Richmond Park and Merton Park.

Mr Sinnott said: "She's no stranger to running long distances, but how she did that and didn't get killed I don't know."

He said the family rescued Bella from a dogs' home last May and her early life experiences have made her wary of unknown adults.

Mr McDonald, an advertising director who met Bella for the first time on Sunday, said: "How she got across the A308 or A3, it blows my mind. It's like there were angels watching over Bella."

Mr Sinnott said: "She's a typical jack russell who likes to chase furry animals, deer and cats. She came back as if nothing had happened.

"I think for her it was just a big adventure."