Police received a report of a distraction theft from a home on Mabel's Furlong in Ledbury on Thursday.
An elderly resident answered her front door to a woman, who stated she had a gift for the resident. The woman was invited in.
The resident left the room to fetch something and returned to find the woman had left. She then discovered that some money had gone from her purse.
The woman who knocked on the door is described as white, about 30 years old, and about 5ft (1.5m) tall. She was wearing a matching brown jacket and brown trousers.
Detective Sergeant Simon Jury said: "We are conducting a full investigation into this incident, during which somebody appears to have exploited the trusting nature of a vulnerable person. The victim was not hurt, but understandably she is very upset.
"While our investigation is ongoing, we would urge anybody with information to come forward. Perhaps you saw a person or group of people acting suspiciously in the area, or knocking door-to-door? You may even have experienced a similar incident yourself.
"Even a small detail could prove useful, so please get in touch."
To provide information, please phone the police non-emergency number 101 and quote incident reference 0118S of 14/12/17. You can also leave information anonymously with the charity Crimestoppers, which is independent of the police. Call Crimestoppers on 0800 555 111 or visit crimestoppers-uk.org.
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