Animal lovers have taken to facebook to condemn a driver spotted with a dog in the back of his open-backed van.

A video shows the animal standing the back of the truck as it travels down the M20, near the turning for the M26.

But Tree Surgeon Dean Marney, from Sidcup, said he had no choice because the pet - named Benji - had gone missing while out on a walk.

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"He's my son's dog" Mr Marney said.

"My son was out walking him and he got away and we went out looking for him - my son, and my wife were in the cab with me."

"We found him near the motorway, and I had no choice. I had to pick him up, and there was no room for him in the cab.

"I'm not that type of person, I don't normally carry him like that. I didn't have a choice."

Benji, who did not seem fazed by the ride, is now safely back home, but many on Facebook have reacted angrily to the video.

Shelley Bennett wrote: "Is it just me, or do you think that's animal cruelty? Lol."

Chirs Bennett wrote:"That's ****ing harsh!!! Imagine he had to emergency break or do a sharp turn, that dog's dead!"

Other posters even say they have contacted the RSPCA.

An RSPCA spokesman confirmed they were investigating.

He said: "The matter has been passed to an RSPCA inspector.

"It is also important that a dog is suitably restrained in a vehicle so it doesn’t distract the driver or injure them if the vehicle stops quickly, as stipulated in the UK Highway Code.

"The RSPCA therefore recommends dogs are both secure and comfortable during transport."