A farmer has had to shoot a dog which escaped from its owner and attacked sheep off Labourham Drove to the south of Cheddar.
The Drove is a popular destination for dog walkers.
But farmer Paul Athay had to take steps to protect part of his flock, which grazes there, on Tuesday afternoon.
The owner of the shot dog was at the scene but was unable to control the animal.
A group of local farmers between Cheddar and Draycott were mobilised to go out and stop it attacking sheep on several properties.
Mr Athay said: “The owner had only had the dog, a rescue animal, for a day when it ran off.
“I know her daughter was upset by what we had to do, but my kids have to see the damage a dog can do to my sheep several times a year. It’s a horrific death for a sheep.”
Sometimes they are killed outright but on many occasions they can be left critically injured for hours, or even days, after being attacked.
Mr Athay has a flock of 1,000 ewes and 800 lambs and has to deal with sheep killing incidents several times a year.
“I was up at Charterhouse a few weeks ago seeing to a flock when I spotted something on the wrong side of a hedge - it turned out to be one of my lambs that had been attacked.
“It had one of its front legs almost torn off, but it was still alive - I had to shoot it.
“From the way it was lying someone had dragged it over the hedge and just dumped it, still alive by the hedge after it had been savaged.”
It is the second time in a month in which has had to shoot dogs attacking sheep in the Cheddar Valley.
He believes the worst types of dogs to chase sheep were not large dogs but labradors and spaniels.
The Labourham Drove incident follows a spate of dog attacks at Shute Shelve where he was forced to shoot a labrador which had escaped from its owners garden while they were at work and attacked a flock.
Mr Athay said: “I know dog owners see my dogs rounding up sheep but they are under my control.
“And they think their dogs are fine and don’t chase sheep, but they do, and that’s only half the problem.
“The main problem is no matter how gentle your dog is, my sheep are terrified of them. They end up drowned in rhynes or wounded and lying in fields for days. I won’t hesitate to shoot a dog if it is worrying my sheep.”
Mr Athay said he loses at least five sheep a year to dog attacks.