Theft claims relating to the vehicle are up 14% since iconic model went out of production in January 2016, it says.
Farmers, who rely on the 4x4 vehicle to farm and tend to livestock, are finding their Land Rovers stripped of parts such as bonnets and doors – or stolen altogether.
Thefts of executive cars and luxury 4x4s have also spiked with the insurer reporting a significant rise in the cost of Range Rover theft in the past year.
NFU Mutual, which works closely with the National Vehicle Intelligence Service (NaVCIS), has traced stolen Range Rovers worth more than £75,000 each.
Some have ended up as far away as Africa and the Far East.
One of the most recent vehicles to be repatriated by NFU Mutual was a Range Rover Sport insured by the company and worth over £60,000.
It was which was seized in Antwerp following an operation coordinated by NFU Mutual and NaVCIS.
Another recovery, of two Range Rovers covered with mattresses and worth over £100,000, was made from a shipping container in Felixstowe.
NFU Mutual vehicle specialist Clive Harris said: “Whether they’re compromising keyless technology or dismantling Defenders, thieves are deploying a range of tactics to feed demand for classic and modern 4 x4s from organised criminal gangs operating around the world.
“While insurance can cover the cost of theft, it does not account for the inconvenience and business interruption experienced.
People in rural areas are feeling increasingly vulnerable and farms, which rely on 4x4s for mobility as part their business, are left particularly hard hit.
“We’re urging owners to ensure they have adequate security measures in place which can range from using aftermarket mechanical immobilisers such as a steering wheel locks to trackers and faraday box solutions, which block out signals.”
According to NFU Mutual claims data, the region with the highest cost of Land Rover Defender thefts last year was the Midlands, followed by the North East and South East England.
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