Farmers are turning to medieval type fortifications to combat a surge in farm thefts.

According to NFU Mutual determined criminal gangs have caused rural crime in the UK to hit its highest level for four years costing some £44.5 million last year.

The gangs are overcoming electronic security measures to grab expensive agricultural equipment.

NFU Mutual's rural affairs expert, Tim Price, said this year's increase in rural crime was caused by a new breed of thieves, using technology and brute force to steal from farms.

He said: "This year we're seeing people bring in things like earth banks - the medieval fortifications last used a thousand years ago."

Examples of the medieval measures being adopted by farmers include:

• Earth banks and ditches. Last used to protect medieval manors, earth works are being installed along field boundaries to stop criminals driving 4x4s onto farmland.

• Reinforced gates. To protect entrances to farmyards from ram raids.

• Protective animals. Animals such as geese and dogs still provide a useful low-tech alarm system, just as they did hundreds of years ago.

One farmer James Gregory from Cheltenham told the BBC he was installing an earth bank in order to deter joyriders and opportunistic thieves.

He said: "It's early days but it's like putting a padlock on a shed: if you were really determined you could still probably break in, but if it just deters a casual person then you're saving a lot of hassle."

In Gloucestershire a special police campaign against rural crime is starting to produce results.

For more details on the rural crime report visit www.nfumutual.co.uk/farming/ruralcrime/