Frustrated police officers have taken farmers to task on amber beacons.

This morning (Thursday), the Devon and Cornwall Roads Policing Team took to social media to tell farmers to use their amber beacons on vehicles.

Officers shared a picture of a the back of a large trailer, noting that there was no flashing amber beacon, despite the trailer being towed along a dual carriageway.

The law states that tractors with a maximum speed that is less than 25mph must have a warning beacon lit.

There are two exceptions to The Road Vehicles Lighting Regulations 1989: vintage tractors registered before January 1, 1947 and tractors simply crossing a dual carriageway directly.

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The officers wrote: "Farmers. It is vital that you ensure you have working amber warning beacons, visible for 360 degrees, if you take agricultural vehicles onto dual carriageways.

"Faster vehicles need advance warning that you are travelling at maximum 25mph to prevent collisions. This one didn't."

The driver was stopped and reported.