Youths riding around a field on a moped may have been responsible for killing a cow by harassing it into a ditch.

Christopher Beckwith and Andrew Collinswood with the body of the cow

The animal became stranded in a ditch in a field in Kennington, off Sandford Lane, where residents say youths regularly ride mopeds. It was unable to drag itself out and died over the weekend.

Steve Chandler, 59, who lives beside the field, said he saw three boys, aged about 15 to 17, messing about on a moped on Friday afternoon chasing cows and sheep. The moped had no number plate and riders were not wearing helmets.

He said: "This time it was a cow. Next time it could be a child that is killed."

He said on Friday, at about 4.30pm, he saw two white youths and one black teenager chasing livestock at the spot where the cow was discovered.

Mr Chandler said antisocial behaviour by youths on mopeds was common during evenings and weekends.

Last summer he saw a moped nearly knock over a small child in the same field.

Farmer Andrew Colinswood, 25, who owns 200 sheep and five cows in the Kennington field, said it was possible yobs on mopeds were responsible. "Kids on mopeds are definitely causing a problem," he said.

He said he had asked the youths to stop. However, there is a right of way which allows walkers and cyclists through the field, meaning there was no means of barring them.

On Friday morning, a sheep was found dead in the same field. But Mr Colinswood and farm worker Christopher Beckwith, 22, who made the discovery, believe the sheep died after being savaged by a dog.

Mr Colinswood warned if problems persisted with dogs harassing livestock he may be forced to shoot them.

The offender could be prosecuted under the Protection of Animals Act which states anyone who "cruelly terrifies" an animal could go to prison for six months and/ or receive a £5,000 fine. Perpetrators could also be prosecuted for criminal damage to a cow.

Call police with information on 08458 505505. Anyone with information about cruelty to animals can call the RSPCA on 08705 555999.