A bogus social worker called to a house in Londonderry on Wednesday asking a woman questions about her children.
Police at Strand Road are keen to hear from anyone who can help identify a bogus caller.
Inspector Jonny Hunter said that at about 11.30am on Wednesday, a man called at a house at Cornshell Fields and claimed to be a social worker asking questions about her children.
Checks established that Social Services had not sent anyone to the house.
The man is described as being about 5ft 8ins tall and of a slim build. He had black hair and was wearing a grey suit. He left the house on foot. He was carrying a black file.
“We are keen to hear from anyone who was in the area on Wednesday morning, or from anyone who was approached in similar circumstances,” a police spokesman said.
“As a reminder, please do not allow any strangers into your home or give them information about yourself or your family.
“Always insist on seeing identification from anyone who calls claiming to be from an official organisation.”
Information can be given to police on the 101 non-emergency number, or by calling Crimestoppers anonymously on 0800 555 111.