More than 40 sheep and lambs have been "professionally butchered" in the latest wave of devastating attacks on livestock.

Criminal gangs looking to sell the meat on the black market are believed to be behind the targeted slaughtering of animals, which has left farmers on the verge of leaving the agricultural industry altogether.

Sheep thefts have escalated since the start of the year, with pedigree animals snatched and a series of four attacks in the past week in Northamptonshire, with carcasses seized in the majority of cases.

At least 10 sheep were killed and stolen on Saturday on Harrington Road, Kelmarsh, and a lamb was discovered tied up with electric fence wire in Boughton Road, Moulton, Northampton.

The county and the area of the Midlands - particularly Warwickshire and Leicestershire - have been the hardest hit by semi-professional thieves.

Farmer Phil Neal said he felt like "giving up" after 14 of his lambs were killed in a field off the A428 between Crick and West Haddon, Northamptonshire, between Sunday afternoon and Monday afternoon.

He described the scene that greeted his family, including his young children, as they did their regular stock check as "the worst thing that my children have witnessed."