Police are linking an incident of a bogus social worker trying to gain access to a four-year-old child in Abingdon with a similar case elsewhere in the county.

Detectives have released an e-fit picture as they appealed for public help to track down the woman, who called at a house in Sherwood Avenue, Abingdon, at 3.30pm on Tuesday.

An e-fit of the suspect

The description of the woman has led officers to investigate whether there are links to a very similar bogus social worker incident, which happened in Kidlington on February 8.

They are also looking into any possible links to a fake social worker reported in the Kennington area of Oxford in October or November of last year.

In the latest incident, when the girl's mother answered the door, the woman said she had come from social services and asked to see the youngster.

The mother was suspicious and refused to let the caller in. When she left, she rang social services, who told her they had no knowledge of her caller.

Police praised the mother, who is not being identified, for her actions and said they were looking at other similar cases to see if they could be linked.

Det Con Chris Hand, of Abingdon CID, said: "We are concerned that this woman could be part of something else.

"We are desperately trying to research other departments that had other previous cases.

"The child's mother fortunately did not allow this woman in. She acted exactly as she should, refusing to let in anyone she did not know.

"We are taking this matter very seriously and would appeal for public help to trace this woman."

Det Con Hand added: "We are chasing up further descriptions from the Kidlington and Kennington incidents at the moment.

"We are not ruling out a link. We are very concerned and we want to make sure people take extra precautions when opening their doors."

The Abingdon bogus social worker is white, in her late 30s to early 40s and about 5ft 4in tall. She had dark hair tied back into a ponytail and dark-coloured eyes.

At the time she called at the house, she was wearing a dark jacket and trousers with a white shirt and hoop earrings. She was also carrying a black leather bag and spoke with a local accent.

Anyone with any information should contact Det Con Hand on 01235 556863 or call the freephone confidential Crimestoppers hotline on 0800 555 111.