There are reports of at least six incidents in the Colchester and Tendring areas in the last two weeks.
The NFU and Essex Police are urging people to remain vigilant, to not engage with unsolicited traders and contact the police if approached.
The scammers are walking onto farmland or telephoning farmers to say they are informing them about roadworks being carried out and forthcoming road closures in the area.
At the end of the conversation, they offer to fill potholes on farm tracks with materials left over from a job earlier in the day for £50. They then carry out work not asked for and demand fees of up to £12,000, threatening violence and damage to property and farm machinery if the farmers do not pay.
They continue to call, harass and threaten people demanding payment.
Intimidation and threats
PC James Nickless, from Essex Police’s Rural Engagement Team, said: “We are aware of several scams being reported at rural locations in Colchester and Tendring in recent days.
“These scams involve an offer of roadworks and/or a dumping of material on properties, followed by intimidating and threatening demands for payment.
“We have upped our patrols in rural areas where these incidents have taken place, and we’d urge anyone with information which could assist us to come forward.
“Our investigation is ongoing and is progressing.”
The NFU is aware of farmers in Colchester, East Bergholt, Great Bentley, Horsley Cross, Great Horkesley and Wix being targeted.
Police have identified a white Iveco tipper truck, which they say is of interest. Officers ask for anyone who has seen this vehicle in relation to this suspicious activity to get in touch.
Police advice to farmers
PC Nickless said: “I understand how upsetting and frustrating such incidents can be, and we’d ask anyone who has experienced a scam like this to notify us immediately.
“Do not hand over any money, reach out to us and provide as much information as possible. By reporting incidents, you are helping us to gather intelligence and build a clear picture of this criminal activity.”
People can contact Essex Police by submitting a report on the police website or by using their online Live Chat service which is available 24 hours-a-day, seven days-a-week. It can be found at the bottom right of the police homepage. Alternatively, call Essex Police on 101.
Police ask people to reference incidents 392 of 2 March, 364 of 3 March and 470 of 4 March.
If someone is present on your property and you feel there is an immediate threat to your safety, call 999.