RSPCA officers have renewed their appeal for help in tracking down the owner of a dog left to suffocate in a rubbish skip.

They hope to prick the conscience of the person who let the border collie die in horrific circumstances - or to encourage people who may know what happened to come forward.

The dog, believed to be aged about nine, was abandoned in a heavy duty refuse sack, tied with twine and weighted down with concrete posts and thrown on top of a pile of rubbish.

RSPCA inspector Garry Palmer was reduced to tears when he found the dog, outside a railway station in Yarm, Teesside. It had to be put to sleep.

He said: "We are absolutely gutted about this. We want to find the person who did this and left the dog to die. It is unbelievable, and one of the most upsetting things that I have ever seen.

"We would encourage anyone who has any information to come forward. Maybe a neighbour's dog has mysteriously disappeared or they recognise the animal.

"We think the dog may have been living outside because of the condition of his fur. Someone must know something."

Anyone who knows anything can call the RSPCA in confidence on 08705 555999.

Officers are currently examining fingerprints found on the refuse sack.

The Northern Echo has decided not to publish a photograph supplied by RSPCA officers showing the full extent of the dog's neglect.