The biggest ever one-day crackdown on 'rip off Norfolk' ended last night with a tough message to conmen: 'We'll hunt you down.'A 50-strong team from five agencies carried out a co-ordinated operation around the county to target dodgy workmen, bogus callers and distraction burglars who prey on vulnerable people, especially the elderly.

The biggest ever one-day crackdown on 'rip off Norfolk' ended last night with a tough message to conmen: 'We'll hunt you down.'

A 50-strong team from five agencies carried out a co-ordinated operation around the county to target dodgy workmen, bogus callers and distraction burglars who prey on vulnerable people, especially the elderly.

It was led by Norfolk Police's Dereham-based Operation Radar team which was set up 10 months ago to tackle the crimes.

Last night it emerged that since the specialist unit was set up there has been a 49pc drop in distraction burglaries and a 275pc rise in calls from the public to report rogue traders as awareness has increased.

Among the worst incidents of people being conned in recent months have been:

*An 85-year-old widow from Beetley, who was quoted �25 to fix a small piece of cement beneath the roof tiles of her home - but after the work was completed she was forced to write a cheque for �2,800 and only stood up to the workman when he later demanded an extra �4,000.

*An elderly man in Cromer who was 'systematically conned' out of nearly �17,000 over a four-month period by a man who befriended him. The man has been charged with four fraud offences.

*An elderly man in Redenhall, near Diss, was duped into handing over �1500 for power tools. Two brothers have been charged with fraud offences.

*An elderly woman in Norwich was charged �1000 for work to her driveway and house which didn't need doing.

Yesterday's operation saw seven vans touring the county and included police officers and officials from trading standards, HM Revenue and Customs, the Environment Agency and local councils.

Final results from the day were still being finalised last night.

But from the reports back from the teams around the county, one man was arrested on suspicion of stealing a trailer in Norwich, 31 traders were stop checked, two people were fined for licence and MOT offences, five waste licences were dealt with by the Environment Agency and a benefit fraud is being investigated.

Det Sgt Pete Jessop, who co-ordinated yesterday's action - said: 'This is the biggest single event that Norfolk has had against rogue traders.

'The county's strong stance against rogue traders, bogus callers and distraction burglars is not a fad and we will continue to hunt them down. Today's show of joint strength by all the agencies across the county shows that we are becoming more and more effective against these people.'

Gary Williamson, who works for Operation Radar as a researcher, said: 'We are trying to dispel the image of them being Del Boys and Arthur Daleys. They are vicious and nasty and prey on people who we need to look after.'

A large part of yesterday's operation was also to reassure people and the teams visited areas which had been previously targeted by bogus callers, rogue traders and distraction burglars.

Officials spoke to businesses and residents and handed out leaflets to them.

The action was welcomed by legitimate workmen.

Brett Crofts, of Eastern Garage Doors of Wormegay, near King's Lynn, was fitting new doors at a house on the Greenfields estate at Dereham and co-operated with the officials.

'It is good that they are doing this. We can all get a bad name because of conmen.'

The action in Norfolk came as part of a national operation to root out conmen.

Det Sgt Jessop said: 'We can work together really well and have done so.

'We are a single hunter unit and looking out for traders who can be rogue traders and bogus callers.'

They were looking for things such as workmen who resurface drives and cut hedges and charge extortionate amounts.

Det Sgt Jessop said: 'We are looking out for those who are conning people and looking to reassure householders and small companies that we are out there to protect them. These offenders are taking money from legitimate traders.'

Conmen use a variety of ruses to trick their way into people's homes or sell them shoddy goods and services often at extortionate prices.

They tour towns and villages seeking out older or vulnerable people hoping their isolation will make them more susceptible to the scams.

Techniques used in the county recently range from selling fish milk or power tools offering building work or posing as officials from a local authority or utility company.

*To contact Norfolk police call 0845 456 4567. For advice on rogue traders call Norfolk Trading Standards' helpline on 0845 404 0506