"If in doubt, keep them out" is the warning being given out by police.

Bogus callers are people who turn up unannounced, with the intention of tricking their way into people's homes or stating the occupiers need building work or maintenance carried out. This is an easy way for them to deceive residents into handing over cash.

There are individuals operating within the area who are deceiving the elderly and vulnerable, claiming to be builders or gardeners carrying out work.

Following this, often poor or unnecessary work is carried out and then demands for large sums of money are requested. The workmen have been known to pressure the occupier into handing over cash or have even driven them to the bank to withdraw money.

Two males are alleged to have called at an address in Queensgate offering to carry out repairs and maintenance to a property costing over £1,200.

Officers say people should always be wary of callers who turn up at unannounced and advise:

• Never feel pressurised into having work done by unannounced callers. If the caller is genuine they won't mind coming back – perhaps when you have had time to consider the offer and have a friend or family member present.

• Never let strangers into your home.

• If you feel work is required, ensure you get quotes from at least three different reputable companies so you can compare prices and choose which company you want to use.

• Never pay for work upfront – only pay when the work has been carried out to a satisfactory standard.

• If you are unhappy with work done, contact your local Trading Standards Department.

• If you suspect the caller is bogus, contact police on 0845 1 25 35 45.

Queensgate Community Beat Manager PC Richard Collopy said: "Residents should always be wary of people who turn up unannounced offering to do work.

"Some may well be genuine tradesmen but others won't be. Our advice is never to give money upfront and if you do want work doing, to always get at least three quotes from reputable companies so you can compare prices.

"He urged anyone who may also have fallen prey to thieves or who may know more about the two workmen to contact him on 07984 316850 or contact their local police station on 0845 1 25 35 45."