Elderly pensioners have been duped into handing over money by a suspected fraudster claiming to need it for an urgeny taxi fare to hospital.
The most recent incident saw a woman in her 90s from The Chase, Chigwell, hand over £40 to the man after inviting him in to her home yesterday, shortly after 1.30pm.
The woman left the suspect alone to get the money and on her return found her bag open but it is unclear what was taken.
Earlier the same day a woman in her 80s, of Mill Lane in Ongar, was persuaded to part with £35 by the suspect who had put his head through an open window of her home.
The man fled the area on receipt of the money.
Police are asking residents to remind elderly relatives not to let strangers into their homes and to avoid handing over cash.
Anyone with information about these incidents can contact police on 101 or Crimestoppers, anonymously on 0800 555 111.