A PET goat had its jaw torn off during a savage attack by a bull terrier in Oak Hill Park.
The goat - one of three in the Pets' Corner at the park in Manchester Road - also had its leg partially ripped off in the incident and had to be put down.
Officials at the park have slammed the "cowardly" dog owner, who they claim ran away after the attack.
Groundsman Keith Armer, of Hyndburn Council's Parks Department, said that he was with one of his colleagues in the park when they were alerted.
He said: "I went into the compound and saw that a dog - a Staffordshire Bull Terrier cross - had got in through the fence and was tearing the goat to pieces. I scared it off and the lad who was with me called the police.
"I managed to get the goat into a pen but it was in a poor state - it had its right foreleg nearly torn off at the hoof and its bottom jaw was completely ripped off. We informed the vet and she put it down."
Mr Armer added that they asked the dog owner to wait but claimed he just called his dog and ran away.
He said: "The police are involved and hopefully they will be able to catch the cowardly scum who let this happen. I've worked on farms and seen animals in distress but never anything like this.
"The lad I work with had to go home as he was so upset - it was horrendous. It was extremely fortunate that there were no people around - but next time it could be a child that this dog gets hold of. I've never felt so angry in my life."
Peter Clegg, works manager at Hyndburn Council, said: "This was a most distressing incident for everybody concerned and to the best of my knowledge the police are now involved.''
Accrington Police confirmed they were investigating.