Police have pleaded with elderly people not to let unknown visitors into their homes after two more women fell prey to bogus callers.

A woman of 85 and another of 94 at separate addresses in Grays were conned out of more than £6,000 between them on Friday. Both incidents happened between 9am and 10am.

Three white men called on a house in Grantham Way, where around £1,000 was taken while the 85-year-old was distracted by the men posing as water board officials.

The other incident occurred in London Road, where one man posed as a water board official and stole £5,000 from the 94-year-old resident.

Police say this man was more forceful because he was working alone. But they also said he was very positive with what he claimed he needed to do in the house, taking advantage of the woman's inability to follow him around at any speed.

Although the descriptions of the men vary, an Essex Police spokeswoman said thieves of this kind often worked in groups and the times, locations and methods used lead them to believe the two incidents may be linked.

The spokeswoman added: "Tragically in both cases the women had the necessary security to their home including spy holes and door chains.

"But once again the victims have not made use of these security systems and have accepted on face value the callers to their door."