MAGISTRATES have warned would-be dog owners to know exactly what they are buying after a family pet that turned out to be a banned breed killed 20 lambs and injured a farmer's partner.

Gemma Wood, 34, had owned the family pet for two years and had always believed it to be a Staffordshire bull terrier, Bradford magistrates heard.

But the dog, known as Mocha, must now be destroyed after trained police officers discovered it was actually a banned pit bull type.

The court was told how the dog had got out of Wood's home in North Dean Road, Keighley, and started worrying sheep in a field at nearby Intake Lane.

The farmer attempted to stop the dog as it attacked his lambs, and his partner Yvett Richardson received bruising injuries and her jeans were ripped as the animal went for her.

Two or three of the lambs died at the scene of the incident which took place on August 25. A further two died due to the distress of the attack and the remainder had to be put down due to their injuries, resulting in a £700 vet bill.

The value of the breeding animals was estimated at £4,000 in total.

Wood pleaded guilty yesterday at Bradford and Keighley Magistrates' Court to being the owner of a dog worrying livestock, being the owners of a dog being dangerously out of control causing injury, and possessing a fighting dog.

She was ordered to complete 80 hours of community work and to pay £500 in compensation to the owner of the sheep, as well as a £180 court charge. Magistrates also ordered that the dog, which was handed over to the authorities following the incident, be destroyed.

Chairman of the bench Brian Outlaw warned: "This is a message that you should tell all your friends who have got dogs that look like yours, because you didn't know you had a banned breed."

Richard Davies, prosecuting, said that Miss Richardson had indicated that this was not the first time the dog had got into the field with the sheep, but that they had given the defendant the benefit of the doubt on these occasions.

"You are not allowed to have a prohibited breed - it's an absolute offence, so whether Miss Wood knew is immaterial.

"There is not always a clear cut distinction between the different breeds of dogs, but the responsibility falls on the owner."

Reg Le Pla, for Wood, said she had been unaware the dog was a banned breed and that she had bought it believing it to be a Staffy.

The dog had regularly played with her three children and had not shown signs of such violence before.

He added that since she got the dog she had installed high fencing around the garden and a warning sign, and believed that someone must have left he gate open that day for the dog to escape.

"This lady, who has had this dog for two years, was not aware of any propensity for violence and ill conduct at all.

 year yesterday for be like a debt. But  didn't find more  friendship assume "She has three children and the dog has never shown any inclination to be violent towards the children, even in rough play.

"She is deeply remorseful about being responsible for this and accepts that the dog is no longer hers, as it is prohibited, and will be destroyed."