Twenty-three sheep have been run over and killed on a farm by a gang of quad bikers operating in the Cotswolds.
Police are investigating reports of up to 30 incidents of vandalism in recent weeks affecting farms in Gloucestershire.
Farm gates have been deliberately smashed open, equipment has been stolen and livestock let loose in a mini crimewave affecting farms.
Farmer Toby Baxter, 43, who has a farm near Cirencester, said 23 sheep were killed in a recent night-time joyrider attack.
He said: “Joyriders drove round the field at night and deliberately ran them over.”
The sheep were part of a flock of 550 grazing on the farm.
“Joyriders drove round the field at night and deliberately ran them over”
Toby Baxter, sheep farmer
The NFU told the BBC that the area had been “plagued by gangs, indiscriminately smashing through gates” at high speed.
NFU Gloucestershire chairman Tanya Robbins said: “Gangs appear riding quad bikes, riding flat out and driving cars, smashing though gates and electric fences – anything that’s in their way.
“They’re going through at such speed, they’re causing criminal damage. They’re also letting out livestock. We’re worried sick.”
Ms Robbins said farms had reported incidents in a 30-mile area around Cheltenham, Winchcombe, Andoversford and Northleach.
Gloucestershire police’s rural crime officer, Simon Clemett, said he would be working closely with the NFU, the farmers involved and other police departments.
“We will be looking at prosecuting for criminal damage to property, including livestock that has been injured or killed,” he said.
“It’s not that we are not interested, we are very interested.
“But if people know this is going on and they’re not calling it in, I would urge them to do so.”
Anyone with information on these incidents is asked to call Gloucestershire police on 101.